diff --git a/file/tests/file_spec.js b/file/tests/file_spec.js
index 19bee95..2347499 100644
--- a/file/tests/file_spec.js
+++ b/file/tests/file_spec.js
@@ -1,5 +1,5 @@
 var assert = require("assert");
-var sys = require("sys");
+var util = require('util');
 var minitest = require("../vendor/minitest.js/minitest");
 var file = require("../lib/main");
 var fs = require("fs");
diff --git a/file/vendor/minitest.js/minitest.js b/file/vendor/minitest.js/minitest.js
index 8a8520c..d508e2b 100644
--- a/file/vendor/minitest.js/minitest.js
+++ b/file/vendor/minitest.js/minitest.js
@@ -1,4 +1,4 @@
-var sys = require("sys");
+var util = require('util');
 var colours = require("./colours");
 
 /* suite */
@@ -9,10 +9,10 @@ function Suite () {
 Suite.prototype.report = function () {
   var suite = this;
   this.contexts.forEach(function(context, index) {
-    sys.puts(context.contextHeader());
+    util.puts(context.contextHeader());
     context.report();
     if (suite.contexts.length === index) {
-      sys.puts("");
+      util.puts("");
     };
   });
 };
@@ -74,9 +74,9 @@ Test.prototype.failed = function (error) {
 
 Test.prototype.report = function () {
   if (this.result) {
-    sys.puts(this.result);
+    util.puts(this.result);
   } else {
-    sys.puts(this.reportNotFinished());
+    util.puts(this.reportNotFinished());
   };
 };
 
@@ -140,7 +140,7 @@ function setupUncaughtExceptionListener () {
   // so we could just set test.result, so everything would be
   // reported properly on the correct place, not in the middle of tests
   process.addListener("uncaughtException", function (error) {
-    sys.puts(Test.prototype.reportError(error));
+    util.puts(Test.prototype.reportError(error));
   });
 };
 
diff --git a/pool/README.md b/pool/README.md
index 0ab4be7..55057de 100644
--- a/pool/README.md
+++ b/pool/README.md
@@ -12,14 +12,14 @@ Pool has two core usage scenarios: creating a pool and creating a set of pools.
 
 <pre>
   var pool = require('pool'),
-      sys = require('sys'),
+      util = require('util'),
       local = pool.createPool('80', 'localhost');
 
   client = local.request('GET', '/', function (request) {
     // You can work with the request here just as you would as if it 
     // was returned from http.createClient
     request.on('end', function () {
-      sys.puts('Request ended');
+      util.puts('Request ended');
     });
   });
 </pre>
@@ -35,7 +35,7 @@ Creating a set of pools can be accomplished using a PoolManager:
     // You can work with the request here just as you would as if it 
     // was returned from http.createClient
     request.on('end', function () {
-      sys.puts('Request ended');
+      util.puts('Request ended');
     });        
   });
 </pre>
\ No newline at end of file
diff --git a/pool/main.js b/pool/main.js
index 774cf6b..69246fb 100644
--- a/pool/main.js
+++ b/pool/main.js
@@ -1,4 +1,4 @@
-var sys = require('sys')
+var util = require('util')
   , http = require('http')
   , events = require('events')
   ;
@@ -13,7 +13,7 @@ function Pool (port, host, https, credentials) {
   this.minClients = 0;
   this.maxClients = 8;
 }
-sys.inherits(Pool, events.EventEmitter);
+util.inherits(Pool, events.EventEmitter);
 Pool.prototype.getClient = function (cb) {
   for (var i=0;i<this.clients.length;i+=1) {
     // Check if the client closed unexpectedly
diff --git a/streams/lib/main.js b/streams/lib/main.js
index 7868651..ec51c71 100644
--- a/streams/lib/main.js
+++ b/streams/lib/main.js
@@ -1,4 +1,4 @@
-var sys = require('sys')
+var util = require('util')
   , events = require('events');
 
 /*
@@ -9,15 +9,15 @@ Simplified API for creating a Stream compatible object that can mutate data comi
 
   // Write 4 chunks at a time.
   var b = [];
-  var filter = sys.createFilter(function (chunk, write) {
+  var filter = util.createFilter(function (chunk, write) {
     if (!chunk || b.length === 4) {
       b.forEach( function (c) {write(c)} );
     } else {
       b.push(chunk);
     }
   });
-  sys.pump(readable, filter);
-  sys.pump(filter, writable);
+  util.pump(readable, filter);
+  util.pump(filter, writable);
 */
 
 function Filter(handler) {
@@ -39,7 +39,7 @@ Filter.prototype.pause = function() {
 Filter.prototype.resume = function() {
   this.emit("resume")
 }
-sys.inherits(Filter, events.EventEmitter)
+util.inherits(Filter, events.EventEmitter)
 
 function createFilter (handler) {
   return new Filter(handler);