diff --git a/src/entities/catalogi/catalogi.mock.ts b/src/entities/catalogi/catalogi.mock.ts
index 57d81e88..11ec77dc 100644
--- a/src/entities/catalogi/catalogi.mock.ts
+++ b/src/entities/catalogi/catalogi.mock.ts
@@ -19,6 +19,7 @@ export const mockCatalogiData = (): TCatalogi[] => [
 			rsin: '987654321',
 			pki: 'PKI-12345-67890',
 		},
+		metadata: ['1', '3'],
 	},
 	{
 		id: '2',
@@ -37,6 +38,7 @@ export const mockCatalogiData = (): TCatalogi[] => [
 			rsin: '987654321',
 			pki: 'PKI-12345-67890',
 		},
+		metadata: [],
 	},
 	{
 		id: '3',
@@ -56,6 +58,7 @@ export const mockCatalogiData = (): TCatalogi[] => [
 			rsin: '987654321',
 			pki: 'PKI-12345-67890',
 		},
+		metadata: ['1', '3'],
 	},
 ]
 
diff --git a/src/entities/catalogi/catalogi.ts b/src/entities/catalogi/catalogi.ts
index dd1d1202..3a51fa2f 100644
--- a/src/entities/catalogi/catalogi.ts
+++ b/src/entities/catalogi/catalogi.ts
@@ -20,6 +20,8 @@ export class Catalogi implements TCatalogi {
         pki: string
     }
 
+	public metadata: string[]
+
 	constructor(data: TCatalogi) {
 		this.hydrate(data)
 	}
@@ -42,6 +44,7 @@ export class Catalogi implements TCatalogi {
 			rsin: '',
 			pki: '',
 		}
+		this.metadata = data.metadata || []
 	}
 
 	/* istanbul ignore next */
@@ -62,6 +65,7 @@ export class Catalogi implements TCatalogi {
 				rsin: z.string(),
 				pki: z.string(),
 			}),
+			metadata: z.string().array(),
 		})
 
 		const result = schema.safeParse({
diff --git a/src/entities/catalogi/catalogi.types.ts b/src/entities/catalogi/catalogi.types.ts
index 47750642..548b3d2b 100644
--- a/src/entities/catalogi/catalogi.types.ts
+++ b/src/entities/catalogi/catalogi.types.ts
@@ -15,4 +15,5 @@ export type TCatalogi = {
         rsin: string
         pki: string
     }
+    metadata: string[]
 }
diff --git a/src/modals/Modals.vue b/src/modals/Modals.vue
index 1e1eb9e7..224a7064 100644
--- a/src/modals/Modals.vue
+++ b/src/modals/Modals.vue
@@ -11,6 +11,7 @@
 		<EditMetaDataPropertyModal />
 		<AddCatalogModal />
 		<EditCatalogModal />
+		<AddCatalogiMetadata />
 		<AddDirectoryModal />
 		<EditListingModal />
 		<AddPublicationDataModal />
@@ -37,6 +38,7 @@ import EditMetaDataPropertyModal from './metaData/EditMetaDataPropertyModal.vue'
 
 import AddCatalogModal from './catalog/AddCatalogModal.vue'
 import EditCatalogModal from './catalog/EditCatalogModal.vue'
+import AddCatalogiMetadata from './catalogiMetadata/AddCatalogiMetadata.vue'
 import AddDirectoryModal from './directory/AddDirectoryModal.vue'
 import EditListingModal from './directory/EditListingModal.vue'
 import AddOrganisationModal from './organisation/AddOrganisationModal.vue'
@@ -59,6 +61,7 @@ export default {
 		EditMetaDataPropertyModal,
 		AddCatalogModal,
 		EditCatalogModal,
+		AddCatalogiMetadata,
 		AddDirectoryModal,
 		EditListingModal,
 		AddPublicationDataModal,
diff --git a/src/modals/catalogiMetadata/AddCatalogiMetadata.vue b/src/modals/catalogiMetadata/AddCatalogiMetadata.vue
new file mode 100644
index 00000000..ca6d4ee1
--- /dev/null
+++ b/src/modals/catalogiMetadata/AddCatalogiMetadata.vue
@@ -0,0 +1,179 @@
+<script setup>
+import { catalogiStore, navigationStore } from '../../store/store.js'
+</script>
+
+<template>
+	<NcModal v-if="navigationStore.modal === 'addCatalogiMetadata'"
+		ref="modalRef"
+		label-id="addCatalogModal"
+		@close="closeModal">
+		<div class="modal__content">
+			<h2>Metadata toevoegen aan Catalogus</h2>
+			<div v-if="success !== null || error">
+				<NcNoteCard v-if="success" type="success">
+					<p>Catalogus succesvol toegevoegd</p>
+				</NcNoteCard>
+				<NcNoteCard v-if="!success" type="error">
+					<p>Er is iets fout gegaan bij het toevoegen van catalogus</p>
+				</NcNoteCard>
+				<NcNoteCard v-if="error" type="error">
+					<p>{{ error }}</p>
+				</NcNoteCard>
+			</div>
+			<div v-if="success === null" class="form-group">
+				<NcSelect v-bind="metaData"
+					v-model="metaData.value"
+					input-label="MetaData"
+					:loading="metaDataLoading"
+					required />
+			</div>
+			<NcButton v-if="success === null"
+				:disabled="!catalogi.title || loading"
+				type="primary"
+				@click="addCatalogMetadata">
+				<template #icon>
+					<NcLoadingIcon v-if="loading" :size="20" />
+					<Plus v-if="!loading" :size="20" />
+				</template>
+				Toevoegen
+			</NcButton>
+		</div>
+	</NcModal>
+</template>
+
+<script>
+import { NcButton, NcModal, NcLoadingIcon, NcNoteCard, NcSelect } from '@nextcloud/vue'
+import Plus from 'vue-material-design-icons/Plus.vue'
+
+export default {
+	name: 'AddCatalogiMetadata',
+	components: {
+		NcModal,
+		NcButton,
+		NcLoadingIcon,
+		NcNoteCard,
+		NcSelect,
+		// Icons
+		Plus,
+	},
+	data() {
+		return {
+			catalogiItem: {
+				title: '',
+				summary: '',
+				description: '',
+				listed: false,
+			},
+			metaData: {},
+			metaDataLoading: false,
+			loading: false,
+			success: null,
+			error: false,
+			errorCode: '',
+		}
+	},
+	mounted() {
+		// catalogiStore.catalogiItem can be false, so only assign catalogiStore.catalogiItem to catalogiItem if its NOT false
+		catalogiStore.catalogiItem && (this.catalogiItem = catalogiStore.catalogiItem)
+	},
+	updated() {
+		if (navigationStore.modal === 'addCatalogiMetadata' && this.hasUpdated) {
+			if (this.catalogiItem.id === catalogiStore.catalogiItem.id) return
+			this.hasUpdated = false
+		}
+		if (navigationStore.modal === 'addCatalogiMetadata' && !this.hasUpdated) {
+			catalogiStore.catalogiItem && (this.catalogiItem = catalogiStore.catalogiItem)
+			this.fetchData(catalogiStore.catalogiItem.id)
+			this.fetchMetaData(catalogiStore.catalogiItem?.metadata || [])
+			this.hasUpdated = true
+		}
+	},
+	methods: {
+		closeModal() {
+			navigationStore.setModal(false)
+			this.catalogi = {
+				title: '',
+				summary: '',
+				description: '',
+				listed: false,
+			}
+		},
+		fetchMetaData(metadataList) {
+			this.metaDataLoading = true
+			fetch('/index.php/apps/opencatalogi/api/metadata', {
+				method: 'GET',
+			})
+				.then((response) => {
+					response.json().then((data) => {
+						const filteredData = data.results.filter((meta) => !metadataList.includes(meta?.id))
+
+						this.metaData = {
+							options: filteredData.map((metaData) => ({
+								id: metaData.id,
+								label: metaData.title,
+							})),
+						}
+					})
+					this.metaDataLoading = false
+				})
+				.catch((err) => {
+					console.error(err)
+					this.metaDataLoading = false
+				})
+		},
+		addCatalogMetadata() {
+			this.loading = true
+			this.error = false
+			fetch(
+				`/index.php/apps/opencatalogi/api/catalogi/${this.catalogi.id}`,
+				{
+					method: 'PUT',
+					headers: {
+						'Content-Type': 'application/json',
+					},
+					body: JSON.stringify({
+						...this.catalogi,
+						metadata: this.catalogi.metadata.push(this.metaData.value.id),
+					}),
+				},
+			)
+				.then((response) => {
+					this.loading = false
+					this.success = response.ok
+					// Lets refresh the catalogiList
+					catalogiStore.refreshCatalogiList()
+					response.json().then((data) => {
+						catalogiStore.setCatalogiItem(data)
+					})
+					// Wait for the user to read the feedback then close the model
+					const self = this
+					setTimeout(function() {
+						self.success = null
+						self.closeModal()
+					}, 2000)
+				})
+				.catch((err) => {
+					this.error = err
+					this.loading = false
+				})
+		},
+	},
+}
+</script>
+
+<style>
+.modal__content {
+    margin: var(--OC-margin-50);
+    text-align: center;
+}
+
+.zaakDetailsContainer {
+    margin-block-start: var(--OC-margin-20);
+    margin-inline-start: var(--OC-margin-20);
+    margin-inline-end: var(--OC-margin-20);
+}
+
+.success {
+    color: green;
+}
+</style>
diff --git a/src/store/modules/configuration.specs.js b/src/store/modules/configuration.specs.js
deleted file mode 100644
index 085b544a..00000000
--- a/src/store/modules/configuration.specs.js
+++ /dev/null
@@ -1,137 +0,0 @@
-/* eslint-disable no-console */
-import { createPinia, setActivePinia } from 'pinia'
-
-import { Configuration } from '../../entities/index.js'
-import { useConfigurationStore } from './configuration.js'
-
-describe(
-	'Metadata Store', () => {
-		beforeEach(
-			() => {
-				setActivePinia(createPinia())
-			},
-		)
-
-		it(
-			'sets configuration item correctly', () => {
-				const store = useConfigurationStore()
-
-				store.setConfigurationItem(testData[0])
-
-				expect(store.configurationItem).toBeInstanceOf(Configuration)
-				expect(store.configurationItem).toEqual(testData[0])
-				expect(store.configurationItem.validate()).toBe(true)
-
-				store.setConfigurationItem(testData[1])
-
-				expect(store.configurationItem).toBeInstanceOf(Configuration)
-				expect(store.configurationItem).not.toEqual(testData[1])
-				expect(store.configurationItem.validate()).toBe(true)
-
-				store.setConfigurationItem(testData[2])
-
-				expect(store.configurationItem).toBeInstanceOf(Configuration)
-				expect(store.configurationItem).toEqual(testData[2])
-				expect(store.configurationItem.validate()).toBe(false)
-			},
-		)
-
-		it(
-			'sets configuration list correctly', () => {
-				const store = useConfigurationStore()
-
-				store.setConfigurationItem(testData)
-
-				expect(store.configurationList).toHaveLength(testData.length)
-
-				expect(store.configurationList[0]).toBeInstanceOf(Configuration)
-				expect(store.configurationList[0]).toEqual(testData[0])
-				expect(store.configurationList[0].validate()).toBe(true)
-
-				expect(store.configurationList[1]).toBeInstanceOf(Configuration)
-				expect(store.configurationList[1]).not.toEqual(testData[1])
-				expect(store.configurationList[1].validate()).toBe(true)
-
-				expect(store.configurationList[2]).toBeInstanceOf(Configuration)
-				expect(store.configurationList[2]).toEqual(testData[2])
-				expect(store.configurationList[2].validate()).toBe(false)
-			},
-		)
-	},
-)
-
-const testData = [
-	{ // full data
-		id: '1',
-		reference: 'ref1',
-		title: 'test 1',
-		summary: 'a short form summary',
-		description: 'a really really long description about this catalogus',
-		image: 'https://example.com/image.jpg',
-		category: 'category1',
-		portal: 'portal1',
-		catalogi: 'catalogi1',
-		metaData: 'meta1',
-		publicationDate: '2024-01-01',
-		modified: '2024-01-02',
-		featured: true,
-		organisation: [{ name: 'Org1' }],
-		data: [{ key: 'value1' }],
-		attachments: ['attachment1'],
-		attachmentCount: 1,
-		schema: 'schema1',
-		status: 'status1',
-		license: 'MIT',
-		themes: 'theme1',
-		anonymization: { anonymized: 'yes', results: 'success' },
-		language: { code: 'en', level: 'native' },
-	},
-	{ // partial data
-		id: '2',
-		reference: 'ref2',
-		title: 'test 2',
-		summary: 'a short form summary',
-		description: 'a really really long description about this catalogus',
-		image: 'https://example.com/image.jpg',
-		category: 'category2',
-		portal: 'portal2',
-		catalogi: 'catalogi2',
-		metaData: 'meta2',
-		publicationDate: '2024-01-01',
-		modified: '2024-01-02',
-		featured: true,
-		organisation: [{ name: 'Org1' }],
-		data: [{ key: 'value1' }],
-		attachments: ['attachment1'],
-		attachmentCount: 1,
-
-		themes: 'theme1',
-		anonymization: { anonymized: 'yes', results: 'success' },
-		language: { code: 'en', level: 'native' },
-	},
-	{ // invalid data
-		id: '3',
-		reference: 'ref3',
-		title: '',
-		summary: 'a short form summary',
-		description: 'a really really long description about this catalogus',
-		image: 'https://example.com/image.jpg',
-		category: 'category3',
-		portal: 'portal3',
-		catalogi: 'catalogi3',
-		metaData: 'meta3',
-		publicationDate: '2024-01-01',
-		modified: '2024-01-02',
-		featured: true,
-		organisation: [{ name: 'Org1' }],
-		data: [{ key: 'value1' }],
-		attachments: ['attachment1'],
-		attachmentCount: 1,
-		schema: 'schema1',
-		status: 'status1',
-		license: 'MIT',
-		themes: 'theme1',
-		anonymization: { anonymized: 'yes', results: 'success' },
-		language: { code: 'en', level: 'native' },
-	},
-]
diff --git a/src/views/catalogi/CatalogiDetails.vue b/src/views/catalogi/CatalogiDetails.vue
index bdc03ef6..7fd2afad 100644
--- a/src/views/catalogi/CatalogiDetails.vue
+++ b/src/views/catalogi/CatalogiDetails.vue
@@ -41,6 +41,12 @@ import { catalogiStore, navigationStore } from '../../store/store.js'
 					</template>
 					Catalogus bekijken
 				</NcActionButton>
+				<NcActionButton @click="navigationStore.setModal('addCatalogiMetadata')">
+					<template #icon>
+						<Plus :size="20" />
+					</template>
+					Metadata toevoegen
+				</NcActionButton>
 				<NcActionButton @click="navigationStore.setDialog('deleteCatalog')">
 					<template #icon>
 						<Delete :size="20" />
@@ -76,6 +82,7 @@ import Pencil from 'vue-material-design-icons/Pencil.vue'
 import Delete from 'vue-material-design-icons/Delete.vue'
 import OpenInApp from 'vue-material-design-icons/OpenInApp.vue'
 import HelpCircleOutline from 'vue-material-design-icons/HelpCircleOutline.vue'
+import Plus from 'vue-material-design-icons/Plus.vue'
 
 export default {
 	name: 'CatalogiDetails',