diff --git a/CHANGELOG.md b/CHANGELOG.md
index 57c5cfc..79fcb73 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Added public function `Find-Certificate` that returns one or more
+  certificates using certificate selector parameters - [Issue #100](https://github.com/dsccommunity/DscResource.Common/issues/100)
+  - Related to [CertificateDsc Issue #272](https://github.com/dsccommunity/CertificateDsc/issues/272).
+
 ## [0.14.0] - 2022-12-31
 
 ### Added
diff --git a/README.md b/README.md
index 4298fcf..6694682 100644
--- a/README.md
+++ b/README.md
@@ -521,6 +521,82 @@ ConvertTo-HashTable -CimInstance $cimInstance
 This creates a array om CimInstances of the class name MSFT_KeyValuePair
 and passes it to ConvertTo-HashTable which returns a hashtable.
 
+### `Find-Certificate`
+
+A common function to find certificates based on multiple search filters,
+including, but not limited to: Thumbprint, Friendly Name, DNS Names,
+Key Usage, Issuers, etc.
+
+Locates one or more certificates using the passed certificate selector
+parameters.
+
+If more than one certificate is found matching the selector criteria,
+they will be returned in order of descending expiration date.
+
+#### Syntax
+
+```plaintext
+Find-Certificate [[-Thumbprint] <String>] [[-FriendlyName] <String>]
+[[-Subject] <String>] [[-DNSName] <String[]>] [[-Issuer] <String>]
+[[-KeyUsage] <String[]>] [[-EnhancedKeyUsage] <String[]>] [[-Store] <String>]
+[[-AllowExpired] <Boolean>] [<CommonParameters>]
+```
+
+### Outputs
+
+**System.Security.Cryptography.X509Certificates.X509Certificate2**
+
+### Example
+
+```PowerShell
+Find-Certificate -Thumbprint '1111111111111111111111111111111111111111'
+```
+
+Return certificate that matches thumbprint.
+
+```PowerShell
+Find-Certificate -KeyUsage 'DataEncipherment', 'DigitalSignature'
+```
+
+Return certificate(s) that have specific key usage.
+
+```PowerShell
+Find-Certificate -DNSName 'www.fabrikam.com', 'www.contoso.com'
+```
+
+Return certificate(s) filtered on specific DNS Names.
+
+```PowerShell
+find-certificate -Subject 'CN=contoso, DC=com'
+```
+
+Return certificate(s) with specific subject.
+
+```PowerShell
+find-certificate -Issuer 'CN=contoso-ca, DC=com' -AllowExpired $true
+```
+
+Return all certificates from specific issuer, including expired certificates.
+
+```PowerShell
+$findCertSplat = @{
+    EnhancedKeyUsage = @('Client authentication','Server Authentication')
+    AllowExpired = $true
+}
+
+Find-Certificate @findCertSplat
+```
+
+Return all certificates that can be used for server or client authentication,
+including expired certificates.
+
+```PowerShell
+Find-Certificate -FriendlyName 'My SSL Cert'
+```
+
+Return certificate based on FriendlyName.
+
+
 ### `Get-ComputerName`
 
 Returns the computer name cross-plattform. The variable `$env:COMPUTERNAME`
diff --git a/source/Public/Find-Certificate.ps1 b/source/Public/Find-Certificate.ps1
new file mode 100644
index 0000000..58523b4
--- /dev/null
+++ b/source/Public/Find-Certificate.ps1
@@ -0,0 +1,189 @@
+<#
+    .SYNOPSIS
+        Locates one or more certificates using the passed certificate selector parameters.
+
+        If more than one certificate is found matching the selector criteria, they will be
+        returned in order of descending expiration date.
+
+    .DESCRIPTION
+        A common function to find certificates based on multiple search filters, including,
+        but not limited to: Thumbprint, Friendly Name, DNS Names, Key Usage, Issuers, etc.
+
+    .PARAMETER Thumbprint
+        The thumbprint of the certificate to find.
+
+    .PARAMETER FriendlyName
+        The friendly name of the certificate to find.
+
+    .PARAMETER Subject
+        The subject of the certificate to find.
+
+    .PARAMETER DNSName
+        The subject alternative name of the certificate to export must contain these values.
+
+    .PARAMETER Issuer
+        The issuer of the certificate to find.
+
+    .PARAMETER KeyUsage
+        The key usage of the certificate to find must contain these values.
+
+    .PARAMETER EnhancedKeyUsage
+        The enhanced key usage of the certificate to find must contain these values.
+
+    .PARAMETER Store
+        The Windows Certificate Store Name to search for the certificate in.
+        Defaults to 'My'.
+
+    .PARAMETER AllowExpired
+        Allows expired certificates to be returned.
+
+    .EXAMPLE
+        Find-Certificate -Thumbprint '1111111111111111111111111111111111111111'
+
+        Return certificate that matches thumbprint.
+
+    .EXAMPLE
+        Find-Certificate -KeyUsage 'DataEncipherment', 'DigitalSignature'
+
+        Return certificate(s) that have specific key usage.
+
+    .EXAMPLE
+        Find-Certificate -DNSName 'www.fabrikam.com', 'www.contoso.com'
+
+        Return certificate(s) filtered on specific DNS Names.
+
+    .EXAMPLE
+        find-certificate -Subject 'CN=contoso, DC=com'
+
+        Return certificate(s) with specific subject.
+
+    .EXAMPLE
+        find-certificate -Issuer 'CN=contoso-ca, DC=com' -AllowExpired $true
+
+        Return all certificates from specific issuer, including expired certificates.
+
+    .EXAMPLE
+        Find-Certificate -EnhancedKeyUsage 'Server Authentication' -AllowExpired $true
+
+        Return all certificates that can be used for "Server Authentication", including expired certificates.
+
+    .EXAMPLE
+        Find-Certificate -FriendlyName 'My IIS Site SSL Cert'
+
+        Return certificate based on FriendlyName.
+
+#>
+function Find-Certificate
+{
+    [CmdletBinding()]
+    [OutputType([System.Security.Cryptography.X509Certificates.X509Certificate2[]])]
+    param
+    (
+        [Parameter()]
+        [System.String]
+        $Thumbprint,
+
+        [Parameter()]
+        [System.String]
+        $FriendlyName,
+
+        [Parameter()]
+        [System.String]
+        $Subject,
+
+        [Parameter()]
+        [System.String[]]
+        $DNSName,
+
+        [Parameter()]
+        [System.String]
+        $Issuer,
+
+        [Parameter()]
+        [System.String[]]
+        $KeyUsage,
+
+        [Parameter()]
+        [System.String[]]
+        $EnhancedKeyUsage,
+
+        [Parameter()]
+        [System.String]
+        $Store = 'My',
+
+        [Parameter()]
+        [Boolean]
+        $AllowExpired = $false
+    )
+
+    $certPath = Join-Path -Path 'Cert:\LocalMachine' -ChildPath $Store
+
+    if (-not (Test-Path -Path $certPath))
+    {
+        # The Certificte Path is not valid
+        New-InvalidArgumentException `
+            -Message ($script:localizedData.CertificatePathError -f $certPath) `
+            -ArgumentName 'Store'
+    } # if
+
+    # Assemble the filter to use to select the certificate
+    $certFilters = @()
+
+    if ($PSBoundParameters.ContainsKey('Thumbprint'))
+    {
+        $certFilters += @('($_.Thumbprint -eq $Thumbprint)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('FriendlyName'))
+    {
+        $certFilters += @('($_.FriendlyName -eq $FriendlyName)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('Subject'))
+    {
+        $certFilters += @('($_.Subject -eq $Subject)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('Issuer'))
+    {
+        $certFilters += @('($_.Issuer -eq $Issuer)')
+    } # if
+
+    if (-not $AllowExpired)
+    {
+        $certFilters += @('(((Get-Date) -le $_.NotAfter) -and ((Get-Date) -ge $_.NotBefore))')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('DNSName'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject $_.DNSNameList.Unicode -DifferenceObject $DNSName | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('KeyUsage'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject ($_.Extensions.KeyUsages -split ", ") -DifferenceObject $KeyUsage | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    if ($PSBoundParameters.ContainsKey('EnhancedKeyUsage'))
+    {
+        $certFilters += @('(@(Compare-Object -ReferenceObject ($_.EnhancedKeyUsageList.FriendlyName) -DifferenceObject $EnhancedKeyUsage | Where-Object -Property SideIndicator -eq "=>").Count -eq 0)')
+    } # if
+
+    # Join all the filters together
+    $certFilterScript = '(' + ($certFilters -join ' -and ') + ')'
+
+    Write-Verbose `
+        -Message ($script:localizedData.SearchingForCertificateUsingFilters -f $store, $certFilterScript) `
+        -Verbose
+
+    $certs = Get-ChildItem -Path $certPath |
+        Where-Object -FilterScript ([ScriptBlock]::Create($certFilterScript))
+
+    # Sort the certificates
+    if ($certs.count -gt 1)
+    {
+        $certs = $certs | Sort-Object -Descending -Property 'NotAfter'
+    } # if
+
+    return $certs
+} # end function Find-Certificate
diff --git a/source/en-US/DscResource.Common.strings.psd1 b/source/en-US/DscResource.Common.strings.psd1
index 8acc2d1..c49bff2 100644
--- a/source/en-US/DscResource.Common.strings.psd1
+++ b/source/en-US/DscResource.Common.strings.psd1
@@ -43,4 +43,8 @@ ConvertFrom-StringData @'
     ## Assert-RequiredCommandParameter
     RequiredCommandParameter_SpecificParametersMustAllBeSet = The parameters '{0}' must all be specified. (DRC0044)
     RequiredCommandParameter_SpecificParametersMustAllBeSetWhenParameterExist = The parameters '{0}' must all be specified if either parameter '{1}' is specified. (DRC0045)
+
+    ## Find-Certificate
+    CertificatePathError = Certificate Path '{0}' is not valid. (DRC0046)
+    SearchingForCertificateUsingFilters = Looking for certificate in Store '{0}' using filter '{1}'. (DRC0047)
 '@
diff --git a/tests/Unit/Public/Find-Certificate.Tests.ps1 b/tests/Unit/Public/Find-Certificate.Tests.ps1
new file mode 100644
index 0000000..796a412
--- /dev/null
+++ b/tests/Unit/Public/Find-Certificate.Tests.ps1
@@ -0,0 +1,522 @@
+[System.Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseDeclaredVarsMoreThanAssignments', '')]
+param ()
+
+BeforeDiscovery {
+    try
+    {
+        if (-not (Get-Module -Name 'DscResource.Test'))
+        {
+            # Assumes dependencies has been resolved, so if this module is not available, run 'noop' task.
+            if (-not (Get-Module -Name 'DscResource.Test' -ListAvailable))
+            {
+                # Redirect all streams to $null, except the error stream (stream 2)
+                & "$PSScriptRoot/../../build.ps1" -Tasks 'noop' 2>&1 4>&1 5>&1 6>&1 > $null
+            }
+
+            # If the dependencies has not been resolved, this will throw an error.
+            Import-Module -Name 'DscResource.Test' -Force -ErrorAction 'Stop'
+        }
+    }
+    catch [System.IO.FileNotFoundException]
+    {
+        throw 'DscResource.Test module dependency not found. Please run ".\build.ps1 -ResolveDependency -Tasks build" first.'
+    }
+}
+
+BeforeAll {
+    $script:moduleName = 'DscResource.Common'
+
+    # Make sure there are not other modules imported that will conflict with mocks.
+    Get-Module -Name $script:moduleName -All | Remove-Module -Force
+
+    # Re-import the module using force to get any code changes between runs.
+    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+
+    $PSDefaultParameterValues['InModuleScope:ModuleName'] = $script:moduleName
+    $PSDefaultParameterValues['Mock:ModuleName'] = $script:moduleName
+    $PSDefaultParameterValues['Should:ModuleName'] = $script:moduleName
+
+    # Dynamic mock content for Get-ChildItem
+    $mockGetChildItem = {
+        switch ( $Path )
+        {
+            'cert:\LocalMachine\My'
+            {
+                return @( $validCertificate )
+            }
+
+            'cert:\LocalMachine\NoCert'
+            {
+                return @()
+            }
+
+            'cert:\LocalMachine\TwoCerts'
+            {
+                return @( $expiredCertificate, $validCertificate )
+            }
+
+            'cert:\LocalMachine\Expired'
+            {
+                return @( $expiredCertificate )
+            }
+
+            default
+            {
+                throw 'mock called with unexpected value {0}' -f $Path
+            }
+        }
+    }
+
+    $mockJoinPath = {
+        return "Cert:\LocalMachine\$ChildPath"
+    }
+
+    $mockTestPath = {
+        return $true
+    }
+}
+
+AfterAll {
+    $PSDefaultParameterValues.Remove('Mock:ModuleName')
+    $PSDefaultParameterValues.Remove('InModuleScope:ModuleName')
+    $PSDefaultParameterValues.Remove('Should:ModuleName')
+
+    Remove-Module -Name $script:moduleName
+}
+
+Describe 'Find-Certificate' -Tag 'FindCertificate' {
+    BeforeAll {
+        Mock -CommandName Get-ChildItem -MockWith $mockGetChildItem
+        Mock -CommandName Test-Path -MockWith $mockTestPath
+        Mock -CommandName Join-Path -MockWith $mockJoinPath
+
+        #Generate test cert object to run against.
+        $certificateDNSNames = @('www.fabrikam.com', 'www.contoso.com')
+        $certificateDNSNamesReverse = @('www.contoso.com', 'www.fabrikam.com')
+        $certificateDNSNamesNoMatch = $certificateDNSNames + @('www.nothere.com')
+
+        $certificateKeyUsage = @('DigitalSignature', 'DataEncipherment')
+        $certificateKeyUsageReverse = @('DataEncipherment', 'DigitalSignature')
+        $certificateKeyUsageNoMatch = $certificateKeyUsage + @('KeyEncipherment')
+
+        $certificateEKU = @('Server Authentication', 'Client authentication')
+        $certificateEKUReverse = @('Client authentication', 'Server Authentication')
+        $certificateEKUNoMatch = $certificateEKU + @('Encrypting File System')
+
+        $certificateSubject = 'CN=contoso, DC=com'
+        $certificateFriendlyName = 'Contoso Test Cert'
+
+        $validThumbprint = 'B994DA47197931EFA3B00CB2DF34E2510E404C8D'
+        $expiredThumbprint = '31343B742B3062CF880487C2125E851E2884D00A'
+        $noCertificateThumbprint = '1111111111111111111111111111111111111111'
+
+        $validCertificate = @{
+            FriendlyName = $certificateFriendlyName
+            Subject = $certificateSubject
+            Thumbprint = $validThumbprint
+            NotBefore = ((Get-Date) - (New-TimeSpan -Days 1))
+            NotAfter = ((Get-Date) + (New-TimeSpan -Days 30))
+            Issuer = $certificateSubject
+
+            DnsNameList = $certificateDNSNames | ForEach-Object {
+                @{
+                    Unicode = $PSItem
+                }
+            }
+
+            Extensions = @{
+                KeyUsages = $certificateKeyUsage -join ", "
+            }
+
+            EnhancedKeyUsageList = $certificateEKU | ForEach-Object {
+                @{
+                    FriendlyName = $PSItem
+                }
+            }
+        }
+
+        $expiredCertificate = $validCertificate.Clone()
+        $expiredCertificate['Thumbprint'] = $expiredThumbprint
+        $expiredCertificate['NotBefore'] = ((Get-Date) - (New-TimeSpan -Days 2))
+        $expiredCertificate['NotAfter'] = ((Get-Date) - (New-TimeSpan -Days 1))
+    }
+
+    Context 'Thumbprint only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Thumbprint $validThumbprint } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Thumbprint only is passed and matching certificate does not exist' {
+        It 'Should not throw exception' {
+
+            { $script:result = Find-Certificate -Thumbprint $noCertificateThumbprint } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'FriendlyName only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -FriendlyName $certificateFriendlyName } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'FriendlyName only is passed and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -FriendlyName 'Does Not Exist' } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Subject only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Subject $certificateSubject } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Subject only is passed and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Subject 'CN=Does Not Exist' } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Issuer only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Issuer $certificateSubject } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Issuer only is passed and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Issuer 'CN=Does Not Exist' } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'DNSName only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -DnsName $certificateDNSNames } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'DNSName only is passed in reversed order and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -DnsName $certificateDNSNamesReverse } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'DNSName only is passed with only one matching DNS name and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -DnsName $certificateDNSNames[0] } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'DNSName only is passed but an entry is missing and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -DnsName $certificateDNSNamesNoMatch } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'KeyUsage only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -KeyUsage $certificateKeyUsage } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'KeyUsage only is passed in reversed order and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -KeyUsage $certificateKeyUsageReverse } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'KeyUsage only is passed with only one matching DNS name and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -KeyUsage $certificateKeyUsage[0] } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'KeyUsage only is passed but an entry is missing and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -KeyUsage $certificateKeyUsageNoMatch } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'EnhancedKeyUsage only is passed and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -EnhancedKeyUsage $certificateEKU } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'EnhancedKeyUsage only is passed in reversed order and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -EnhancedKeyUsage $certificateEKUReverse } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'EnhancedKeyUsage only is passed with only one matching DNS name and matching certificate exists' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -EnhancedKeyUsage $certificateEKU[0] } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'EnhancedKeyUsage only is passed but an entry is missing and matching certificate does not exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -EnhancedKeyUsage $certificateEKUNoMatch } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'Store only is passed but the path to the certificate store does not exist' {
+        BeforeAll {
+            Mock -CommandName Test-Path -MockWith { return $false }
+        }
+        It 'Should throw exception' {
+            { $script:result = Find-Certificate -Store "MockWillForceFailureOfTestPath" } | Should -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 0 -Scope "context"
+        }
+    }
+
+    Context 'Thumbprint only is passed and matching certificate does not exist in the store' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -Thumbprint $validThumbprint -Store 'NoCert' } | Should -Not -Throw
+        }
+
+        It 'Should return null' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'FriendlyName only is passed and both valid and expired certificates exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -FriendlyName $certificateFriendlyName -Store 'TwoCerts' } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $validThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'FriendlyName only is passed and only expired certificates exist' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -FriendlyName $certificateFriendlyName -Store 'Expired' } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result | Should -BeNullOrEmpty
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke -CommandName Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke -CommandName Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+
+    Context 'FriendlyName only is passed and only expired certificates exist but allowexpired passed' {
+        It 'Should not throw exception' {
+            { $script:result = Find-Certificate -FriendlyName $certificateFriendlyName -Store 'Expired' -AllowExpired:$true } | Should -Not -Throw
+        }
+
+        It 'Should return expected certificate' {
+            $script:result.Thumbprint | Should -Be $expiredThumbprint
+        }
+
+        It 'Should call expected mocks' {
+            Should -Invoke Test-Path -Exactly -Times 1 -Scope "context"
+            Should -Invoke Get-ChildItem -Exactly -Times 1 -Scope "context"
+        }
+    }
+}