diff --git a/examples/update-on-finish.js b/examples/update-on-finish.js
new file mode 100644
index 0000000..b3170e8
--- /dev/null
+++ b/examples/update-on-finish.js
@@ -0,0 +1,17 @@
+var ProgressBar = require('..');
+
+var bar = new ProgressBar('  [:bar]', {
+  complete: '=',
+  incomplete: '-',
+  total: 20,
+  callback: function () {
+    bar.config({ complete: '▓' });
+  }
+});
+
+var id = setInterval(function (){
+  bar.tick();
+  if (bar.complete) {
+    clearInterval(id);
+  }
+}, 100);
diff --git a/lib/node-progress.js b/lib/node-progress.js
index 8eb0740..c70b145 100644
--- a/lib/node-progress.js
+++ b/lib/node-progress.js
@@ -56,22 +56,28 @@ function ProgressBar(fmt, options) {
   }
 
   this.fmt = fmt;
-  this.curr = options.curr || 0;
-  this.total = options.total;
-  this.width = options.width || this.total;
-  this.clear = options.clear
-  this.chars = {
-    complete   : options.complete || '=',
-    incomplete : options.incomplete || '-',
-    head       : options.head || (options.complete || '=')
-  };
-  this.renderThrottle = options.renderThrottle !== 0 ? (options.renderThrottle || 16) : 0;
+  this.config(options);
   this.lastRender = -Infinity;
-  this.callback = options.callback || function () {};
   this.tokens = {};
   this.lastDraw = '';
 }
 
+/**
+ * Configures (or reconfigures) the progress bar. Only those options that are specified
+ * in the argument are updated. See the constructor function for information on available options.
+ */
+ProgressBar.prototype.config = function (options) {
+  updateConfig(this, options, 'curr', 0);
+  updateConfig(this, options, 'total');
+  updateConfig(this, options, 'width', this.total);
+  updateConfig(this, options, 'clear');
+  this.chars = this.chars || {};
+  updateConfig(this.chars, options, 'complete', '=');
+  updateConfig(this.chars, options, 'incomplete', '-');
+  updateConfig(this, options, 'renderThrottle', 16);
+  updateConfig(this, options, 'callback', function () {});
+}
+
 /**
  * "tick" the progress bar with optional `len` and optional `tokens`.
  *
@@ -98,10 +104,10 @@ ProgressBar.prototype.tick = function(len, tokens){
 
   // progress complete
   if (this.curr >= this.total) {
-    this.render(undefined, true);
     this.complete = true;
-    this.terminate();
     this.callback(this);
+    this.render(undefined, true);
+    this.terminate();
     return;
   }
 };
@@ -162,7 +168,7 @@ ProgressBar.prototype.render = function (tokens, force) {
 
   /* add head to the complete string */
   if(completeLength > 0)
-    complete = complete.slice(0, -1) + this.chars.head;
+    complete = complete.slice(0, -1) + (this.chars.head || this.chars.complete);
 
   /* fill in the actual progress bar */
   str = str.replace(':bar', complete + incomplete);
@@ -234,3 +240,22 @@ ProgressBar.prototype.terminate = function () {
     this.stream.write('\n');
   }
 };
+
+/**
+ * Helper function used to configure one property of a target based on the same property
+ * of an options object, or from a default value if not present in either the target or the
+ * options.
+ * 
+ * @param {object} target The object to set properties on.
+ * @param {object} options The object that contains the configuration properties.
+ * @param {String} property The name of the property to configure.
+ * @param {*} [defValue] The default value. If not specified, `undefined`.
+ */
+function updateConfig(target, options, property, defValue) {
+  if (options.hasOwnProperty(property)) {
+    target[property] = options[property];
+  } else if (!target.hasOwnProperty(property)) {
+    target[property] = defValue;
+  }
+}
+
diff --git a/package.json b/package.json
index bb81fa0..ba569d7 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "progress",
-  "version": "2.0.3",
+  "version": "2.1.0",
   "description": "Flexible ascii progress bar",
   "repository": {
     "type": "git",