diff --git a/routes/component-configuration/config_methods.go b/routes/component-configuration/config_methods.go
index 767b76c..92ec26c 100644
--- a/routes/component-configuration/config_methods.go
+++ b/routes/component-configuration/config_methods.go
@@ -131,7 +131,6 @@ func (m *ComponentConfiguration) delete() error {
 	}
 
 	// remove association between ComponentConfiguration and Scenario
-	// ComponentConfiguration itself is not deleted from DB, it remains as "dangling"
 	err = db.Model(&so).Association("ComponentConfigurations").Delete(m).Error
 	if err != nil {
 		return err
@@ -143,6 +142,32 @@ func (m *ComponentConfiguration) delete() error {
 		return err
 	}
 
+	// Get Signals of InputMapping and delete them
+	var InputMappingSignals []database.Signal
+	err = db.Model(m).Related(&InputMappingSignals, "InputMapping").Error
+	if err != nil {
+		return err
+	}
+	for sig, _ := range InputMappingSignals {
+		err = db.Delete(&sig).Error
+		if err != nil {
+			return err
+		}
+	}
+
+	// Get Signals of OutputMapping and delete them
+	var OutputMappingSignals []database.Signal
+	err = db.Model(m).Related(&OutputMappingSignals, "OutputMapping").Error
+	if err != nil {
+		return err
+	}
+	for sig, _ := range OutputMappingSignals {
+		err = db.Delete(&sig).Error
+		if err != nil {
+			return err
+		}
+	}
+
 	// delete component configuration
 	err = db.Delete(m).Error
 	if err != nil {
diff --git a/routes/dashboard/dashboard_methods.go b/routes/dashboard/dashboard_methods.go
index 2a9b438..913b93c 100644
--- a/routes/dashboard/dashboard_methods.go
+++ b/routes/dashboard/dashboard_methods.go
@@ -30,9 +30,9 @@ type Dashboard struct {
 	database.Dashboard
 }
 
-func (v *Dashboard) save() error {
+func (d *Dashboard) save() error {
 	db := database.GetDB()
-	err := db.Create(v).Error
+	err := db.Create(d).Error
 	return err
 }
 
@@ -90,8 +90,20 @@ func (d *Dashboard) delete() error {
 	// remove association between Dashboard and Scenario
 	err = db.Model(&sim).Association("Dashboards").Delete(d).Error
 
-	// Dashboard itself is not deleted from DB, it remains as "dangling"
-	// TODO: delete dashboard and associated widgets
+	// get all widgets of the dashboard
+	var widgets []database.Widget
+	err = db.Order("ID asc").Model(d).Related(&widgets, "Widgets").Error
+	if err != nil {
+		return err
+	}
+
+	// Delete widgets
+	for widget, _ := range widgets {
+		err = db.Delete(&widget).Error
+	}
+
+	// Delete dashboard
+	err = db.Delete(d).Error
 
 	return err
 }
diff --git a/routes/signal/signal_methods.go b/routes/signal/signal_methods.go
index eddf1c5..dfbd1ce 100644
--- a/routes/signal/signal_methods.go
+++ b/routes/signal/signal_methods.go
@@ -107,7 +107,6 @@ func (s *Signal) delete() error {
 	}
 
 	// remove association between Signal and ComponentConfiguration
-	// Signal itself is not deleted from DB, it remains as "dangling"
 	if s.Direction == "in" {
 		err = db.Model(&m).Association("InputMapping").Delete(s).Error
 		if err != nil {
@@ -117,6 +116,9 @@ func (s *Signal) delete() error {
 		// Reduce length of mapping by 1
 		var newInputLength = m.InputLength - 1
 		err = db.Model(m).Update("InputLength", newInputLength).Error
+		if err != nil {
+			return err
+		}
 
 	} else {
 		err = db.Model(&m).Association("OutputMapping").Delete(s).Error
@@ -127,7 +129,13 @@ func (s *Signal) delete() error {
 		// Reduce length of mapping by 1
 		var newOutputLength = m.OutputLength - 1
 		err = db.Model(m).Update("OutputLength", newOutputLength).Error
+		if err != nil {
+			return err
+		}
 	}
 
+	// Delete signal
+	err = db.Delete(s).Error
+
 	return err
 }
diff --git a/routes/widget/widget_methods.go b/routes/widget/widget_methods.go
index 98eb40f..ff58c6a 100644
--- a/routes/widget/widget_methods.go
+++ b/routes/widget/widget_methods.go
@@ -96,10 +96,13 @@ func (w *Widget) delete() error {
 	}
 
 	// remove association between Dashboard and Widget
-	// Widget itself is not deleted from DB, it remains as "dangling"
 	err = db.Model(&dab).Association("Widgets").Delete(w).Error
+	if err != nil {
+		return err
+	}
 
-	// TODO: What about files that belong to a widget? Keep them or remove them here?
+	// Delete Widget
+	err = db.Delete(w).Error
 
 	return err
 }