diff --git a/src/Paket.Core/NugetConvert.fs b/src/Paket.Core/NugetConvert.fs
index 1d9ee5f0f3..de888f19d1 100644
--- a/src/Paket.Core/NugetConvert.fs
+++ b/src/Paket.Core/NugetConvert.fs
@@ -8,7 +8,6 @@ open System.Xml
 open Paket.Domain
 open Paket.Logging
 open Paket.Xml
-open Paket.NuGetV2
 open Paket.PackageSources
 open Paket.Requirements
 open Chessie.ErrorHandling
@@ -67,12 +66,12 @@ let private getKeyValueList (node : XmlNode) =
         | _ -> None)
 
 type NugetConfig = 
-    { PackageSources : list<string * Auth option>
+    { PackageSources : Map<string, string * Auth option>
       PackageRestoreEnabled : bool
       PackageRestoreAutomatic : bool }
 
     static member empty =
-        { PackageSources = [] 
+        { PackageSources = Map.empty
           PackageRestoreEnabled = false 
           PackageRestoreAutomatic = false }
 
@@ -120,12 +119,15 @@ type NugetConfig =
             |> Option.toList
             |> List.collect getKeyValueList
             |> List.filter (fun (key,_) -> Set.contains key disabledSources |> not)
-            |> List.map (fun (key,value) -> String.quoted value, getAuth key)
-
+            |> List.map (fun (key,value) -> key, (String.quoted value, getAuth key))
+            |> Map.ofList
+            
         { PackageSources = if clearSources then sources
                            else 
-                               nugetConfig.PackageSources @ sources
-                               |> List.distinct
+                              Map.fold 
+                                (fun acc k v -> Map.add k v acc)
+                                nugetConfig.PackageSources
+                                sources
           PackageRestoreEnabled = 
             match configNode |> getNode "packageRestore" |> Option.bind (tryGetValue "enabled") with
             | Some value -> bool.Parse(value)
@@ -271,7 +273,11 @@ let createDependenciesFileR (rootDirectory : DirectoryInfo) nugetEnv mode =
 
     let create() =
         let sources = 
-            if nugetEnv.NugetConfig.PackageSources = [] then [Constants.DefaultNugetStream,None] else nugetEnv.NugetConfig.PackageSources
+            if nugetEnv.NugetConfig.PackageSources = Map.empty then [ Constants.DefaultNugetStream, None ]
+            else 
+                (nugetEnv.NugetConfig.PackageSources
+                 |> Map.toList
+                 |> List.map snd)
             |> List.map (fun (n, auth) -> n, auth |> Option.map (CredsMigrationMode.toAuthentication mode n))
             |> List.map (fun source -> 
                             try source |> PackageSource.Parse |> ok
diff --git a/src/Paket.Core/PublicAPI.fs b/src/Paket.Core/PublicAPI.fs
index fcdd07872f..6555c6b68e 100644
--- a/src/Paket.Core/PublicAPI.fs
+++ b/src/Paket.Core/PublicAPI.fs
@@ -277,7 +277,7 @@ type Dependencies(dependenciesFileName: string) =
     member this.GetDefinedNuGetFeeds() : string list =
         let configured =
             match NuGetConvert.NugetEnv.readNugetConfig(this.RootDirectory) with
-            | Result.Ok(config,_) -> config.PackageSources |> List.map fst
+            | Result.Ok(config,_) -> config.PackageSources |> Map.toList |> List.map (snd >> fst)
             | _ -> []
         Constants.DefaultNugetStream :: configured
         |> Set.ofSeq
diff --git a/tests/Paket.Tests/NuGetConfig/ConfigWithDisabledFeedFromUpstream.xml b/tests/Paket.Tests/NuGetConfig/ConfigWithDisabledFeedFromUpstream.xml
new file mode 100644
index 0000000000..643a8b8e53
--- /dev/null
+++ b/tests/Paket.Tests/NuGetConfig/ConfigWithDisabledFeedFromUpstream.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageRestore>
+    <add key="enabled" value="True" />
+    <add key="automatic" value="True" />
+  </packageRestore>
+  <packageSources>
+    <add key="nuget.org" value="https://www.nuget.org/api/v2/" />
+  </packageSources>
+  <disabledPackageSources>
+    <add key="MyGetDuality" value="true" />
+  </disabledPackageSources>
+  <activePackageSource>
+    <add key="nuget.org" value="https://www.nuget.org/api/v2/" />
+  </activePackageSource>
+</configuration>
\ No newline at end of file
diff --git a/tests/Paket.Tests/NuGetConfig/NuGetConfigSpecs.fs b/tests/Paket.Tests/NuGetConfig/NuGetConfigSpecs.fs
index 57768eecd2..c4693fd0e5 100644
--- a/tests/Paket.Tests/NuGetConfig/NuGetConfigSpecs.fs
+++ b/tests/Paket.Tests/NuGetConfig/NuGetConfigSpecs.fs
@@ -32,9 +32,10 @@ let ``can detect encrypted passwords in nuget.config``() =
     parse "NuGetConfig/PasswordConfig.xml" 
     |> shouldEqual
         { PackageSources = 
-            [ "https://www.nuget.org/api/v2/",None
-              "https://tc/httpAuth/app/nuget/v1/FeedService.svc/",
-                      Some { Username = "notty"; Password = "secret" } ]
+            [ "https://www.nuget.org/api/v2/", ("https://www.nuget.org/api/v2/",None)
+              "tc", ("https://tc/httpAuth/app/nuget/v1/FeedService.svc/",
+                            Some { Username = "notty"; Password = "secret" } ) ]
+            |> Map.ofList
           PackageRestoreEnabled = false
           PackageRestoreAutomatic = false }
 
@@ -42,10 +43,11 @@ let ``can detect encrypted passwords in nuget.config``() =
 let ``can detect cleartextpasswords in nuget.config``() = 
     parse "NuGetConfig/ClearTextPasswordConfig.xml" 
     |> shouldEqual
-        { PackageSources = 
-            [ "https://www.nuget.org/api/v2/",None
-              "https://nuget/somewhere/",
-                      Some { Username = "myUser"; Password = "myPassword" } ]
+        { PackageSources =
+            [ "https://www.nuget.org/api/v2/", ("https://www.nuget.org/api/v2/",None)
+              "somewhere", ("https://nuget/somewhere/",
+                            Some { Username = "myUser"; Password = "myPassword" } ) ]
+            |> Map.ofList 
           PackageRestoreEnabled = false
           PackageRestoreAutomatic = false }
 
@@ -54,6 +56,24 @@ let ``ignores disabled nuget feed`` () =
     parse "NuGetConfig/ConfigWithDisabledFeed.xml"
     |> shouldEqual
         { PackageSources = 
-            [ "https://www.nuget.org/api/v2/",None]
+            [ "nuget.org", ("https://www.nuget.org/api/v2/",None) ]
+            |> Map.ofList
+          PackageRestoreEnabled = true
+          PackageRestoreAutomatic = true }
+
+[<Test>]
+let ``ignores disabled nuget feed from upstream`` () =
+    let upstream = 
+        { NugetConfig.empty with
+            PackageSources = 
+                [ "MyGetDuality", ("https://www.myget.org/F/6416d9912a7c4d46bc983870fb440d25/", None) ]
+                |> Map.ofList }
+    let next = NugetConfig.getConfigNode (FileInfo "NugetConfig/ConfigWithDisabledFeedFromUpstream.xml") |> Trial.returnOrFail
+    let overridden = NugetConfig.overrideConfig upstream next
+    overridden
+    |> shouldEqual
+        { PackageSources = 
+            [ "nuget.org", ("https://www.nuget.org/api/v2/",None) ]
+            |> Map.ofList
           PackageRestoreEnabled = true
-          PackageRestoreAutomatic = true }
\ No newline at end of file
+          PackageRestoreAutomatic = true }
diff --git a/tests/Paket.Tests/Paket.Tests.fsproj b/tests/Paket.Tests/Paket.Tests.fsproj
index 837a294a51..3a71635cc6 100644
--- a/tests/Paket.Tests/Paket.Tests.fsproj
+++ b/tests/Paket.Tests/Paket.Tests.fsproj
@@ -188,10 +188,13 @@
     <Content Include="NuGetConfig\PasswordConfig.xml">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>
+    <Compile Include="NuGetConfig\NuGetConfigSpecs.fs" />
     <Content Include="NuGetConfig\ConfigWithDisabledFeed.xml">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
-    <Compile Include="NuGetConfig\NuGetConfigSpecs.fs" />
+    <Content Include="NuGetConfig\ConfigWithDisabledFeedFromUpstream.xml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
     <Content Include="JSON-LD\Rx-PlatformServices.json">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>