diff --git a/index.js b/index.js
index 3a2c5cf..54683b9 100644
--- a/index.js
+++ b/index.js
@@ -32,7 +32,9 @@ function ConnectionPool(poolConfig, connectionConfig) {
     var connection = new PooledConnection(pool, connectionConfig);
     pool.inUseConnections.push(connection);
 
-    callback(connection);
+    process.nextTick(function() {
+      callback(connection);
+    });
   };
 
   return {
diff --git a/package.json b/package.json
index eb4629e..47c623b 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,8 @@
   "license": "MIT",
   "devDependencies": {
     "tedious": "0.0.7",
-    "mocha": "1.6.0"
+    "mocha": "1.6.0",
+    "async": "0.1.22"
   },
   "licenses": "MIT"
 }
diff --git a/test/connection-pool.test.js b/test/connection-pool.test.js
index a25004f..541b867 100644
--- a/test/connection-pool.test.js
+++ b/test/connection-pool.test.js
@@ -1,5 +1,7 @@
 var assert = require('assert')
+var async = require('async')
 var ConnectionPool = require('../index');
+var Request = require('tedious').Request;
 
 var connectionConfig = {
   userName: 'test',
@@ -9,18 +11,93 @@ var connectionConfig = {
 
 describe('ConnectionPool', function() {
   describe('one connection', function() {
-    it('should connect and end', function(done) {
-      var cp = new ConnectionPool({maxSize: 2}, connectionConfig);
+    var poolSize = 1;
 
-      cp.requestConnection(function (connection) {
-        connection.on('connect', function(err) {
-          connection.close();
+    it('should connect, and end', function(done) {
+      var pool = new ConnectionPool({maxSize: poolSize}, connectionConfig);
+
+      requestConnectionAndClose(pool, function() {
+        done();
+      });
+    });
+
+    it('should connect, select, and end', function(done) {
+      var pool = new ConnectionPool({maxSize: poolSize}, connectionConfig);
+
+      requestConnectionSelectAndClose(pool, function() {
+        done();
+      });
+    });
+  });
+
+  describe('multiple connections within pool maxSize', function() {
+    var poolSize = 5;
+
+    it('should connect, and end', function(done) {
+      var pool = new ConnectionPool({maxSize: poolSize}, connectionConfig);
+
+      function doIt(done) {
+        requestConnectionAndClose(pool, function() {
+          done();
         });
+      }
+
+      var functions = [];
+      for (var f = 0; f < poolSize; f++) {
+        functions.push(doIt);
+      }
+
+      async.parallel(functions, done);
+    });
 
-        connection.on('end', function(err) {
+    it('should connect, select, and end', function(done) {
+      var pool = new ConnectionPool({maxSize: poolSize}, connectionConfig);
+
+      function doIt(done) {
+        requestConnectionSelectAndClose(pool, function() {
           done();
         });
-      });
-    })
-  })
-})
+      }
+
+      var functions = [];
+      for (var f = 0; f < poolSize; f++) {
+        functions.push(doIt);
+      }
+
+      async.parallel(functions, done);
+    });
+  });
+});
+
+function requestConnectionAndClose(pool, done) {
+  pool.requestConnection(function (connection) {
+    connection.on('connect', function(err) {
+      connection.close();
+    });
+
+    connection.on('end', function(err) {
+      done();
+    });
+  });
+}
+
+function requestConnectionSelectAndClose(pool, done) {
+  pool.requestConnection(function (connection) {
+    var request = new Request('select 42', function(err, rowCount) {
+        assert.strictEqual(rowCount, 1)
+        connection.close()
+    });
+
+    request.on('row', function(columns) {
+        assert.strictEqual(columns[0].value, 42)
+    });
+
+    connection.on('connect', function(err) {
+      connection.execSql(request)
+    });
+
+    connection.on('end', function(err) {
+      done();
+    });
+  });
+}