diff --git a/js/feature/mergedTrack.js b/js/feature/mergedTrack.js
index ca4f180d8..0402611b1 100644
--- a/js/feature/mergedTrack.js
+++ b/js/feature/mergedTrack.js
@@ -40,6 +40,8 @@ class MergedTrack extends TrackBase {
         this.featureType = 'numeric'
         this.paintAxis = paintAxis
         this.graphType = config.graphType
+
+        this._alpha = this.config.alpha || 0.5
     }
 
     init(config) {
@@ -49,7 +51,6 @@ class MergedTrack extends TrackBase {
         super.init(config)
     }
 
-
     async postInit() {
 
         this.tracks = []
@@ -69,7 +70,6 @@ class MergedTrack extends TrackBase {
             }
         }
 
-        this.alpha = this.config.alpha || 0.5
         this.flipAxis = this.config.flipAxis ? this.config.flipAxis : false
         this.logScale = this.config.logScale ? this.config.logScale : false
         this.autoscale = this.config.autoscale || this.config.max === undefined
@@ -91,6 +91,14 @@ class MergedTrack extends TrackBase {
         return Promise.all(p)
     }
 
+    set alpha(alpha) {
+        this._alpha = alpha
+    }
+
+    get alpha() {
+        return this._alpha
+    }
+
     get height() {
         return this._height
     }
diff --git a/js/ui/menuUtils.js b/js/ui/menuUtils.js
index a0aa5b302..521f09dcc 100644
--- a/js/ui/menuUtils.js
+++ b/js/ui/menuUtils.js
@@ -132,17 +132,29 @@ function isVisibilityWindowType(track) {
     return hasVizWindow || vizWindowTypes.has(track.type)
 }
 
-
 function overlayTrackAlphaAdjustmentMenuItem() {
 
     const container = DOMUtils.div()
     container.innerText = 'Adjust Alpha'
-    
-    function click(e) {
-        console.log(`The Overlay track has ${ this.config.tracks.length } layers`)
+
+    function dialogPresentationHandler (e) {
+
+        const callback = value => {
+            this.alpha = parseFloat(value)
+            this.updateViews()
+        }
+
+        const config =
+            {
+                label: 'Adjust Alpha',
+                value: 0.5,
+                callback
+            }
+
+        this.browser.inputDialog.present(config, e)
     }
 
-    return { object: $(container), click }
+    return { object: $(container), dialog:dialogPresentationHandler }
 }
 
 function trackSeparationMenuItem() {