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diff --git a/src/csharp/Grpc.Core/GrpcEnvironment.cs b/src/csharp/Grpc.Core/GrpcEnvironment.cs
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+++ b/src/csharp/Grpc.Core/GrpcEnvironment.cs
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+#region Copyright notice and license
+
+// Copyright 2015, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#endregion
+
+using System;
+using System.Runtime.InteropServices;
+using Grpc.Core.Internal;
+
+namespace Grpc.Core
+{
+    /// <summary>
+    /// Encapsulates initialization and shutdown of gRPC library.
+    /// </summary>
+    public class GrpcEnvironment
+    {
+        const int THREAD_POOL_SIZE = 4;
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern void grpcsharp_init();
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern void grpcsharp_shutdown();
+
+        static object staticLock = new object();
+        static volatile GrpcEnvironment instance;
+
+        readonly GrpcThreadPool threadPool;
+        bool isClosed;
+
+        /// <summary>
+        /// Makes sure GRPC environment is initialized. Subsequent invocations don't have any
+        /// effect unless you call Shutdown first.
+        /// Although normal use cases assume you will call this just once in your application's
+        /// lifetime (and call Shutdown once you're done), for the sake of easier testing it's
+        /// allowed to initialize the environment again after it has been successfully shutdown.
+        /// </summary>
+        public static void Initialize() {
+            lock(staticLock)
+            {
+                if (instance == null)
+                {
+                    instance = new GrpcEnvironment();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Shuts down the GRPC environment if it was initialized before.
+        /// Repeated invocations have no effect.
+        /// </summary>
+        public static void Shutdown()
+        {
+            lock(staticLock)
+            {
+                if (instance != null)
+                {
+                    instance.Close();
+                    instance = null;
+                }
+            }
+        }
+
+        internal static GrpcThreadPool ThreadPool
+        {
+            get
+            {
+                var inst = instance;
+                if (inst == null)
+                {
+                    throw new InvalidOperationException("GRPC environment not initialized");
+                }
+                return inst.threadPool;
+            }
+        }
+
+        /// <summary>
+        /// Creates gRPC environment.
+        /// </summary>
+        private GrpcEnvironment()
+        {
+            grpcsharp_init();
+            threadPool = new GrpcThreadPool(THREAD_POOL_SIZE);
+            threadPool.Start();
+            // TODO: use proper logging here
+            Console.WriteLine("GRPC initialized.");
+        }
+
+        /// <summary>
+        /// Shuts down this environment.
+        /// </summary>
+        private void Close()
+        {
+            if (isClosed)
+            {
+                throw new InvalidOperationException("Close has already been called");
+            }
+            threadPool.Stop();
+            grpcsharp_shutdown();
+            isClosed = true;
+
+            // TODO: use proper logging here
+            Console.WriteLine("GRPC shutdown.");
+        }
+    }
+}
+