diff --git a/lib/core.js b/lib/core.js
index d4d7a390a..f99260b34 100644
--- a/lib/core.js
+++ b/lib/core.js
@@ -44,12 +44,16 @@ var Archiver = function(format, options) {
 
   Transform.call(this, options);
 
-  this._entries = [];
   this._format = false;
   this._module = false;
   this._pending = 0;
   this._pointer = 0;
 
+  this._entriesCount = 0;
+  this._entriesProcessedCount = 0;
+  this._fsEntriesTotalBytes = 0;
+  this._fsEntriesProcessedBytes = 0;
+
   this._queue = async.queue(this._onQueueTask.bind(this), 1);
   this._queue.drain = this._onQueueDrain.bind(this);
 
@@ -106,10 +110,17 @@ Archiver.prototype._append = function(filepath, data) {
 
   data.sourcePath = filepath;
   task.data = data;
+  this._entriesCount++;
 
   if (data.stats && data.stats instanceof fs.Stats) {
     task = this._updateQueueTaskWithStats(task, data.stats);
-    if (task) this._queue.push(task);
+    if (task) {
+      if (data.stats.size) {
+        this._fsEntriesTotalBytes += data.stats.size;
+      }
+
+      this._queue.push(task);
+    }
   } else {
     this._statQueue.push(task);
   }
@@ -190,7 +201,26 @@ Archiver.prototype._moduleAppend = function(source, data, callback) {
      * @type {EntryData}
      */
     this.emit('entry', data);
-    this._entries.push(data);
+    this._entriesProcessedCount++;
+
+    if (data.stats && data.stats.size) {
+      this._fsEntriesProcessedBytes += data.stats.size;
+    }
+
+    /**
+     * @event Archiver#progress
+     * @type {ProgressData}
+     */
+    this.emit('progress', {
+      entries: {
+        total: this._entriesCount,
+        processed: this._entriesProcessedCount
+      },
+      fs: {
+        totalBytes: this._fsEntriesTotalBytes,
+        processedBytes: this._fsEntriesProcessedBytes
+      }
+    });
 
     setImmediate(callback);
   }.bind(this));
@@ -399,8 +429,13 @@ Archiver.prototype._onStatQueueTask = function(task, callback) {
     task = this._updateQueueTaskWithStats(task, stats);
 
     if (task) {
+      if (stats.size) {
+          this._fsEntriesTotalBytes += stats.size;
+      }
+
       this._queue.push(task);
     }
+
     setImmediate(callback);
   }.bind(this));
 };
@@ -528,6 +563,7 @@ Archiver.prototype.append = function(source, data) {
     return this;
   }
 
+  this._entriesCount++;
   this._queue.push({
     data: data,
     source: source
@@ -808,6 +844,7 @@ Archiver.prototype.symlink = function(filepath, target) {
     data.linkname = target.replace(/\\/g, '/');
     data.sourceType = 'buffer';
 
+    this._entriesCount++;
     this._queue.push({
         data: data,
         source: new Buffer(0)
@@ -877,3 +914,13 @@ module.exports = Archiver;
  * @property {fs.Stats} [stats] Sets the fs stat data for this entry allowing
  * for reduction of fs stat calls when stat data is already known.
  */
+
+/**
+ * @typedef {Object} ProgressData
+ * @property {Object} entries
+ * @property {Number} entries.total Number of entries that have been appended.
+ * @property {Number} entries.processed Number of entries that have been processed.
+ * @property {Object} fs
+ * @property {Number} fs.totalBytes Number of bytes that have been appended. (based on fs.Stats)
+ * @property {Number} fs.processedBytes Number of bytes that have been processed. (based on fs.Stats)
+ */
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