Index: binaries/data/config/default.cfg
===================================================================
--- binaries/data/config/default.cfg
+++ binaries/data/config/default.cfg
@@ -370,6 +370,7 @@
 aurasrange = true                 ; Display aura range overlays of selected units and structures
 healrange = true                  ; Display heal range overlays of selected units
 rankabovestatusbar = true         ; Show rank icons above status bars
+experiencestatusbar = true        ; Show an experience status bar above each selected unit
 respoptooltipsort = 0             ; Sorting players in the resources and population tooltip by value (0 - no sort, -1 - ascending, 1 - descending)
 
 [gui.session.minimap]
Index: binaries/data/mods/public/gui/options/options.json
===================================================================
--- binaries/data/mods/public/gui/options/options.json
+++ binaries/data/mods/public/gui/options/options.json
@@ -492,6 +492,12 @@
 			},
 			{
 				"type": "boolean",
+				"label": "Experience status bar",
+				"tooltip": "Show an experience status bar above each selected unit.",
+				"config": "gui.session.experiencestatusbar"
+			},
+			{
+				"type": "boolean",
 				"label": "Detailed Tooltips",
 				"tooltip": "Show detailed tooltips for trainable units in unit-producing buildings.",
 				"config": "showdetailedtooltips"
Index: binaries/data/mods/public/gui/session/selection.js
===================================================================
--- binaries/data/mods/public/gui/session/selection.js
+++ binaries/data/mods/public/gui/session/selection.js
@@ -19,7 +19,8 @@
 	Engine.GuiInterfaceCall("SetStatusBars", {
 		"entities": ents,
 		"enabled": enabled,
-		"showRank": Engine.ConfigDB_GetValue("user", "gui.session.rankabovestatusbar") == "true"
+		"showRank": Engine.ConfigDB_GetValue("user", "gui.session.rankabovestatusbar") == "true",
+		"showExperience": Engine.ConfigDB_GetValue("user", "gui.session.experiencestatusbar") == "true"
 	});
 }
 
Index: binaries/data/mods/public/gui/session/session.js
===================================================================
--- binaries/data/mods/public/gui/session/session.js
+++ binaries/data/mods/public/gui/session/session.js
@@ -1366,7 +1366,8 @@
 	Engine.GuiInterfaceCall("SetStatusBars", {
 		"entities": entities,
 		"enabled": g_ShowAllStatusBars && !remove,
-		"showRank": Engine.ConfigDB_GetValue("user", "gui.session.rankabovestatusbar") == "true"
+		"showRank": Engine.ConfigDB_GetValue("user", "gui.session.rankabovestatusbar") == "true",
+		"showExperience": Engine.ConfigDB_GetValue("user", "gui.session.experiencestatusbar") == "true"
 	});
 }
 
Index: binaries/data/mods/public/simulation/components/GuiInterface.js
===================================================================
--- binaries/data/mods/public/simulation/components/GuiInterface.js
+++ binaries/data/mods/public/simulation/components/GuiInterface.js
@@ -851,7 +851,7 @@
 		let cmpStatusBars = Engine.QueryInterface(ent, IID_StatusBars);
 		if (!cmpStatusBars)
 			continue;
-		cmpStatusBars.SetEnabled(cmd.enabled, cmd.showRank);
+		cmpStatusBars.SetEnabled(cmd.enabled, cmd.showRank, cmd.showExperience);
 
 		let cmpAuras = Engine.QueryInterface(ent, IID_Auras);
 		if (!cmpAuras)
Index: binaries/data/mods/public/simulation/components/Promotion.js
===================================================================
--- binaries/data/mods/public/simulation/components/Promotion.js
+++ binaries/data/mods/public/simulation/components/Promotion.js
@@ -166,6 +166,8 @@
 		}
 		this.Promote(promotedTemplateName);
 	}
+
+	Engine.PostMessage(this.entity, MT_ExperienceChanged, {});
 };
 
 Promotion.prototype.OnValueModification = function(msg)
Index: binaries/data/mods/public/simulation/components/StatusBars.js
===================================================================
--- binaries/data/mods/public/simulation/components/StatusBars.js
+++ binaries/data/mods/public/simulation/components/StatusBars.js
@@ -6,7 +6,7 @@
 	"<element name='BarWidth'>" +
 		"<data type='decimal'/>" +
 	"</element>" +
-	"<element name='BarHeight'>" +
+	"<element name='BarHeight' a:help='Height of a normal sized bar. Some bars are scaled accordingly.'>" +
 		"<data type='decimal'/>" +
 	"</element>" +
 	"<element name='HeightOffset'>" +
@@ -21,6 +21,7 @@
  * provide the right methods.
  */
 StatusBars.prototype.Sprites = [
+	"ExperienceBar",
 	"PackBar",
 	"ResourceSupplyBar",
 	"CaptureBar",
@@ -33,6 +34,7 @@
 {
 	this.enabled = false;
 	this.showRank = false;
+	this.showExperience = false;
 
 	// Whether the status bars used the player colors anywhere (e.g. in the capture bar)
 	this.usedPlayerColors = false;
@@ -54,14 +56,15 @@
 	this.auraSources = data.auraSources;
 };
 
-StatusBars.prototype.SetEnabled = function(enabled, showRank)
+StatusBars.prototype.SetEnabled = function(enabled, showRank, showExperience)
 {
 	// Quick return if no change
-	if (enabled == this.enabled && showRank == this.showRank)
+	if (enabled == this.enabled && showRank == this.showRank && showExperience == this.showExperience)
 		return;
 
 	this.enabled = enabled;
 	this.showRank = showRank;
+	this.showExperience = showExperience;
 
 	// Update the displayed sprites
 	this.RegenerateSprites();
@@ -107,6 +110,12 @@
 		this.RegenerateSprites();
 };
 
+StatusBars.prototype.OnExperienceChanged = function()
+{
+	if (this.enabled)
+		this.RegenerateSprites();
+};
+
 StatusBars.prototype.UpdateColor = function()
 {
 	if (this.usedPlayerColors)
@@ -127,11 +136,11 @@
 /**
  * Generic piece of code to add a bar.
  */
-StatusBars.prototype.AddBar = function(cmpOverlayRenderer, yoffset, type, amount)
+StatusBars.prototype.AddBar = function(cmpOverlayRenderer, yoffset, type, amount, heightMultiplier = 1)
 {
 	// Size of health bar (in world-space units)
 	let width = +this.template.BarWidth;
-	let height = +this.template.BarHeight;
+	let height = +this.template.BarHeight * heightMultiplier;
 
 	// World-space offset from the unit's position
 	let offset = { "x": 0, "y": +this.template.HeightOffset, "z": 0 };
@@ -157,6 +166,18 @@
 	return height * 1.2;
 };
 
+StatusBars.prototype.AddExperienceBar = function(cmpOverlayRenderer, yoffset)
+{
+	if (!this.enabled || !this.showExperience)
+		return 0;
+
+	let cmpPromotion = Engine.QueryInterface(this.entity, IID_Promotion);
+	if (!cmpPromotion || !cmpPromotion.GetCurrentXp() || !cmpPromotion.GetRequiredXp())
+		return 0;
+
+	return this.AddBar(cmpOverlayRenderer, yoffset, "pack", cmpPromotion.GetCurrentXp() / cmpPromotion.GetRequiredXp(), 2/3);
+};
+
 StatusBars.prototype.AddPackBar = function(cmpOverlayRenderer, yoffset)
 {
 	if (!this.enabled)
Index: binaries/data/mods/public/simulation/components/interfaces/Promotion.js
===================================================================
--- binaries/data/mods/public/simulation/components/interfaces/Promotion.js
+++ binaries/data/mods/public/simulation/components/interfaces/Promotion.js
@@ -1 +1,7 @@
 Engine.RegisterInterface("Promotion");
+
+/**
+ * Message of the form {}
+ * sent from Promotion component whenever the experience changes.
+ */
+Engine.RegisterMessageType("ExperienceChanged");