diff --git a/package-lock.json b/package-lock.json
index 00a34f04ba..184f15af9e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -5,7 +5,7 @@
   "requires": true,
   "packages": {
     "": {
-      "version": "4.0.0",
+      "version": "4.1.0",
       "dependencies": {
         "@angular/animations": "^9.1.12",
         "@angular/cdk": "^9.2.4",
diff --git a/src/app/main/dialog/dialog.component.html b/src/app/main/dialog/dialog.component.html
index 4d3d1d28c0..44bcfca612 100644
--- a/src/app/main/dialog/dialog.component.html
+++ b/src/app/main/dialog/dialog.component.html
@@ -216,12 +216,9 @@
     <div *ngSwitchCase="'editResourceClass'">
         <app-dialog-header [title]="data.title" [subtitle]="data.subtitle">
         </app-dialog-header>
-        <p class="todo" [innerHtml]="notYetImplemented"></p>
-        <mat-dialog-actions>
-            <button mat-button mat-dialog-close class="cancel-button center" [mat-dialog-close]="false">
-                Cancel
-            </button>
-        </mat-dialog-actions>
+        <app-resource-class-form [iri]="data.id" [name]="data.title" [projectIri]="data.project"
+            [showResourceClassForm]="true" [edit]="true" (closeDialog)="dialogRef.close()">
+        </app-resource-class-form>
     </div>
 
     <div *ngSwitchCase="'deleteResourceClass'">
@@ -243,7 +240,7 @@
         <app-dialog-header [title]="data.title" [subtitle]="data.subtitle">
         </app-dialog-header>
         <app-resource-class-form [iri]="data.id" [name]="data.title" [projectIri]="data.project"
-            [showResourceClassForm]="false" [edit]="true" (closeDialog)="dialogRef.close()" (updateParent)="replaceTitle($event)">
+            [showResourceClassForm]="false" [edit]="true" (closeDialog)="dialogRef.close()">
         </app-resource-class-form>
     </div>
 
diff --git a/src/app/project/ontology/ontology.component.html b/src/app/project/ontology/ontology.component.html
index 1a5ae96168..99bec80683 100644
--- a/src/app/project/ontology/ontology.component.html
+++ b/src/app/project/ontology/ontology.component.html
@@ -86,7 +86,7 @@ <h3 class="mat-title" [matTooltip]="ontology.id">{{ontology?.label}}</h3>
                 <span class="ontology-actions">
                     <p class="mat-caption space-reducer">Data model configuration</p>
                     <!-- TODO: remove following span as soon edit mode is implemented; it's only for tooltip to use with disabled button  -->
-                    <span [matTooltip]="'Edit ontology is not yet implemented'" matTooltipPosition="above">
+                    <span [matTooltip]="'Edit data model info (not yet implemented)'" matTooltipPosition="above">
                         <button mat-button [disabled]="!ontology.lastModificationDate" [disabled]="true"
                             (click)="$event.stopPropagation(); openOntologyForm('editOntology', ontology.id)">
                             <!-- <mat-icon>edit</mat-icon> -->
@@ -107,7 +107,7 @@ <h3 class="mat-title" [matTooltip]="ontology.id">{{ontology?.label}}</h3>
 
             <div class="ontology-editor-subheader">
                 <p *ngIf="!ontology.lastModificationDate" class="note warning center">
-                    This ontology can't be edited because of missing "lastModificationDate"!
+                    This data model can't be edited because of missing "lastModificationDate"!
                 </p>
                 <!-- button to select and add new resource class to the ontology -->
                 <div class="add-resource-class"
@@ -137,14 +137,14 @@ <h4 mat-card-title [matTooltip]="resClass.label" matTooltipPosition="above">
                                     {{resClass.label | dspTruncate: 24}}</h4>
                                 <span class="fill-remaining-space"></span>
                                 <button mat-icon-button [matMenuTriggerFor]="resClassMenu"
-                                    [matTooltip]="(ontology.lastModificationDate ? null : 'This ontology can\'t be edited because of missing lastModificationDate!')"
+                                    [matTooltip]="(ontology.lastModificationDate ? null : 'This data model can\'t be edited because of missing lastModificationDate!')"
                                     matTooltipPosition="above">
                                     <mat-icon>more_horiz</mat-icon>
                                 </button>
                                 <mat-menu #resClassMenu="matMenu" xPosition="before">
-                                    <button mat-menu-item [disabled]="!ontology.lastModificationDate" [disabled]="true"
+                                    <button mat-menu-item [disabled]="!ontology.lastModificationDate"
                                         (click)="openResourceClassForm('editResourceClass', {iri: resClass.id, name: '', label: resClass.label})">
-                                        Edit info (not yet implemented)
+                                        Edit resource class info
                                     </button>
                                     <button mat-menu-item [disabled]="!ontology.lastModificationDate"
                                         (click)="updateCard(resClass)">
diff --git a/src/app/project/ontology/ontology.component.ts b/src/app/project/ontology/ontology.component.ts
index 157feb0a6b..fa37062bbb 100644
--- a/src/app/project/ontology/ontology.component.ts
+++ b/src/app/project/ontology/ontology.component.ts
@@ -237,7 +237,7 @@ export class OntologyComponent implements OnInit {
 
         this.loadOntology = true;
 
-        this._dspApiConnection.v2.onto.getOntology(id).subscribe(
+        this._dspApiConnection.v2.onto.getOntology(id, true).subscribe(
             (response: ReadOntology) => {
 
                 this.ontology = response;
@@ -309,9 +309,9 @@ export class OntologyComponent implements OnInit {
     /**
      * Opens resource class form
      * @param mode
-     * @param subClassOf
+     * @param resClassInfo (could be subClassOf (create mode) or resource class itself (edit mode))
      */
-    openResourceClassForm(mode: 'createResourceClass' | 'editResourceClass', subClassOf: DefaultClass): void {
+    openResourceClassForm(mode: 'createResourceClass' | 'editResourceClass', resClassInfo: DefaultClass): void {
 
         // set cache for ontology and lists
         this.setCache();
@@ -323,7 +323,7 @@ export class OntologyComponent implements OnInit {
             position: {
                 top: '112px'
             },
-            data: { id: subClassOf.iri, title: subClassOf.label, subtitle: 'Customize resource class', mode: mode, project: this.project.id }
+            data: { id: resClassInfo.iri, title: resClassInfo.label, subtitle: 'Customize resource class', mode: mode, project: this.project.id }
         };
 
         const dialogRef = this._dialog.open(
diff --git a/src/app/project/ontology/resource-class-form/resource-class-form.component.html b/src/app/project/ontology/resource-class-form/resource-class-form.component.html
index 4d7a0f4229..bb4a14fe15 100644
--- a/src/app/project/ontology/resource-class-form/resource-class-form.component.html
+++ b/src/app/project/ontology/resource-class-form/resource-class-form.component.html
@@ -12,7 +12,7 @@
                 <!-- label -->
                 <div class="large-field string-literal-container">
                     <dsp-string-literal-input [placeholder]="'Label *'" [value]="resourceClassLabels"
-                        (enter)="nextStep($event)" (dataChanged)="handleData($event, 'labels')">
+                        (enter)="(edit ? submitData($event) : nextStep($event))" (dataChanged)="handleData($event, 'labels')">
                     </dsp-string-literal-input>
                     <mat-hint class="string-literal-error" *ngIf="formErrors.label">
                         {{ formErrors.label }}
@@ -21,7 +21,7 @@
 
                 <!-- description -->
                 <div class="large-field string-literal-container more-space-top">
-                    <dsp-string-literal-input [placeholder]="'Comment'" [value]="resourceClassComments"
+                    <dsp-string-literal-input [placeholder]="'Comment *'" [value]="resourceClassComments"
                         [textarea]="true" (dataChanged)="handleData($event, 'comments')"></dsp-string-literal-input>
                 </div>
             </div>
@@ -35,10 +35,17 @@
                 </span>
                 <span class="fill-remaining-space"></span>
                 <span>
-                    <button mat-raised-button type="button" color="primary" [disabled]="!resourceClassLabels.length"
-                        (click)="nextStep($event)">
-                        Next
-                    </button>
+                    <button *ngIf="!edit" mat-raised-button type="button" color="primary" [disabled]="!resourceClassLabels.length || !resourceClassComments.length"
+                         (click)="nextStep($event)">
+                         Next
+                     </button>
+                     <button *ngIf="edit" mat-raised-button type="button" color="primary" [disabled]="!resourceClassLabels.length || !resourceClassComments.length"
+                         (click)="submitData($event)">
+                         <dsp-progress-indicator [color]="'white'" [status]="0" *ngIf="loading" class="submit-progress">
+                         </dsp-progress-indicator>
+                         <mat-icon *ngIf="error && !loading">close</mat-icon>
+                         {{error ? 'Failed' : 'Update'}}
+                     </button>
                 </span>
             </div>
         </div>
diff --git a/src/app/project/ontology/resource-class-form/resource-class-form.component.ts b/src/app/project/ontology/resource-class-form/resource-class-form.component.ts
index e87ae3241c..4dfa56e0f9 100644
--- a/src/app/project/ontology/resource-class-form/resource-class-form.component.ts
+++ b/src/app/project/ontology/resource-class-form/resource-class-form.component.ts
@@ -15,7 +15,9 @@ import {
     ResourcePropertyDefinitionWithAllLanguages,
     StringLiteral,
     UpdateOntology,
-    UpdateResourceClassCardinality
+    UpdateResourceClassCardinality,
+    UpdateResourceClassComment,
+    UpdateResourceClassLabel
 } from '@dasch-swiss/dsp-js';
 import { StringLiteralV2 } from '@dasch-swiss/dsp-js/src/models/v2/string-literal-v2';
 import { DspApiConnectionToken } from '@dasch-swiss/dsp-ui';
@@ -122,7 +124,8 @@ export class ResourceClassFormComponent implements OnInit, OnDestroy, AfterViewC
 
     // form errors on the following fields:
     formErrors = {
-        'label': ''
+        'label': '',
+        'comment': ''
     };
 
     // in case of form error: show message
@@ -130,6 +133,9 @@ export class ResourceClassFormComponent implements OnInit, OnDestroy, AfterViewC
         'label': {
             'required': 'Label is required.'
         },
+        'comment': {
+            'required': 'Comment is required.'
+        }
     };
 
     lastModificationDate: string;
@@ -202,26 +208,43 @@ export class ResourceClassFormComponent implements OnInit, OnDestroy, AfterViewC
         this._resourceClassFormService.resetProperties();
 
         if (this.edit) {
-            // edit mode
-            // get resource class and property definition first
-
-            // get list of ontology properties
-            const ontoProperties: PropertyDefinition[] = this.ontology.getAllPropertyDefinitions();
 
-            // find prop cardinality in resource class
-            const ontoClasses: ClassDefinition[] = this.ontology.getAllClassDefinitions();
-            Object.keys(ontoClasses).forEach(key => {
-                if (ontoClasses[key].id === this.iri) {
-
-                    this._resourceClassFormService.setProperties(ontoClasses[key], ontoProperties);
+            if (this.showResourceClassForm) {
+                // edit mode: res class info (label and comment)
+                // get resource class info
+                const resourceClasses: ResourceClassDefinitionWithAllLanguages[] = this.ontology.getClassDefinitionsByType(ResourceClassDefinitionWithAllLanguages);
+                Object.keys(resourceClasses).forEach(key => {
+                    if (resourceClasses[key].id === this.iri) {
+                        this.resourceClassLabels = resourceClasses[key].labels;
+                        this.resourceClassComments = resourceClasses[key].comments;
+                    }
+                });
+                this.resourceClassFormSub = this._resourceClassFormService.resourceClassForm$
+                    .subscribe(resourceClass => {
+                        this.resourceClassForm = resourceClass;
+                    });
+                this.resourceClassForm.valueChanges.subscribe(data => this.onValueChanged(data));
 
-                    this.resourceClassFormSub = this._resourceClassFormService.resourceClassForm$
-                        .subscribe(resourceClass => {
-                            this.resourceClassForm = resourceClass;
-                            this.properties = this.resourceClassForm.get('properties') as FormArray;
-                        });
-                }
-            });
+            } else {
+                // edit mode: res class cardinality
+                // get list of ontology properties
+                const ontoProperties: PropertyDefinition[] = this.ontology.getAllPropertyDefinitions();
+
+                // find prop cardinality in resource class
+                const ontoClasses: ClassDefinition[] = this.ontology.getAllClassDefinitions();
+                Object.keys(ontoClasses).forEach(key => {
+                    if (ontoClasses[key].id === this.iri) {
+
+                        this._resourceClassFormService.setProperties(ontoClasses[key], ontoProperties);
+
+                        this.resourceClassFormSub = this._resourceClassFormService.resourceClassForm$
+                            .subscribe(resourceClass => {
+                                this.resourceClassForm = resourceClass;
+                                this.properties = this.resourceClassForm.get('properties') as FormArray;
+                            });
+                    }
+                });
+            }
 
         } else {
             // create mode
@@ -344,9 +367,58 @@ export class ResourceClassFormComponent implements OnInit, OnDestroy, AfterViewC
     submitData() {
         this.loading = true;
         if (this.edit) {
-            // edit mode
-            // submit properties and set cardinality
-            this.submitProps(this.resourceClassForm.value.properties, this.iri);
+
+            if (this.showResourceClassForm) {
+                // edit mode: res class info (label and comment)
+                // label
+                const onto4Label = new UpdateOntology<UpdateResourceClassLabel>();
+                onto4Label.id = this.ontology.id;
+                onto4Label.lastModificationDate = this.lastModificationDate;
+
+                const updateLabel = new UpdateResourceClassLabel();
+                updateLabel.id = this.iri;
+                updateLabel.labels = this.resourceClassLabels;
+                onto4Label.entity = updateLabel;
+
+                // comment
+                const onto4Comment = new UpdateOntology<UpdateResourceClassComment>();
+                onto4Comment.id = this.ontology.id;
+
+                const updateComment = new UpdateResourceClassComment();
+                updateComment.id = this.iri;
+                updateComment.comments = this.resourceClassComments;
+                onto4Comment.entity = updateComment;
+
+                this._dspApiConnection.v2.onto.updateResourceClass(onto4Label).subscribe(
+                    (classLabelResponse: ResourceClassDefinitionWithAllLanguages) => {
+                        this.lastModificationDate = classLabelResponse.lastModificationDate;
+                        onto4Comment.lastModificationDate = this.lastModificationDate;
+
+                        this._dspApiConnection.v2.onto.updateResourceClass(onto4Comment).subscribe(
+                            (classCommentResponse: ResourceClassDefinitionWithAllLanguages) => {
+                                this.lastModificationDate = classCommentResponse.lastModificationDate;
+
+                                // close the dialog box
+                                this.loading = false;
+                                this.closeDialog.emit();
+                            },
+                            (error: ApiResponseError) => {
+                                this._errorHandler.showMessage(error);
+                            }
+                        )
+
+                    },
+                    (error: ApiResponseError) => {
+                        this._errorHandler.showMessage(error);
+                    }
+                );
+
+
+            } else {
+                // edit mode: res class cardinality
+                // submit properties and set cardinality
+                this.submitProps(this.resourceClassForm.value.properties, this.iri);
+            }
 
         } else {
             // create mode
@@ -363,7 +435,7 @@ export class ResourceClassFormComponent implements OnInit, OnDestroy, AfterViewC
 
             const newResClass = new CreateResourceClass();
 
-            newResClass.name = uniqueClassName
+            newResClass.name = uniqueClassName;
             newResClass.label = this.resourceClassLabels;
             newResClass.comment = this.resourceClassComments;
             newResClass.subClassOf = [this.iri];