diff --git a/ext/taj/taj.c b/ext/taj/taj.c
index 621f8c7..1731365 100644
--- a/ext/taj/taj.c
+++ b/ext/taj/taj.c
@@ -192,6 +192,36 @@ rb_connection_add(VALUE self, VALUE rb_key, VALUE rb_value, VALUE ttl, VALUE fla
   return (rc == MEMCACHED_SUCCESS);
 }
 
+static VALUE
+rb_connection_inc(VALUE self, VALUE rb_key, VALUE rb_value)
+{
+  Taj_ctx *ctx = get_ctx(self);
+  char *mkey = StringValuePtr(rb_key);
+  uint32_t offset = NUM2UINT(rb_value);
+  uint64_t new_number;
+
+  memcached_increment(ctx->memc, mkey, strlen(mkey), offset, &new_number);
+  // handle rc not success
+  // (rc == MEMCACHED_SUCCESS);
+
+  return INT2NUM(new_number);
+}
+
+static VALUE
+rb_connection_dec(VALUE self, VALUE rb_key, VALUE rb_value)
+{
+  Taj_ctx *ctx = get_ctx(self);
+  char *mkey = StringValuePtr(rb_key);
+  uint32_t offset = NUM2UINT(rb_value);
+  uint64_t new_number;
+
+  memcached_decrement(ctx->memc, mkey, strlen(mkey), offset, &new_number);
+  // handle rc not success
+  // (rc == MEMCACHED_SUCCESS);
+
+  return INT2NUM(new_number);
+}
+
 void Init_taj(void)
 {
   rb_mTaj = rb_define_module("Taj");
@@ -207,6 +237,8 @@ void Init_taj(void)
   rb_define_method(cConnection, "get_multi", rb_connection_get_multi, 1);
   rb_define_method(cConnection, "delete", rb_connection_delete, 1);
   rb_define_method(cConnection, "add", rb_connection_add, 4);
+  rb_define_method(cConnection, "increment", rb_connection_inc, 2);
+  rb_define_method(cConnection, "decrement", rb_connection_dec, 2);
 
   Taj_Server = rb_define_class_under(rb_mTaj, "Server", rb_cObject);
 
diff --git a/lib/memcached/client.rb b/lib/memcached/client.rb
index 66489fd..d86789c 100644
--- a/lib/memcached/client.rb
+++ b/lib/memcached/client.rb
@@ -57,6 +57,14 @@ module Memcached
       connection.add(key, value, ttl, flags)
     end
 
+    def increment(key, offset = 1)
+      connection.increment(key, offset)
+    end
+
+    def decrement(key, offset = 1)
+      connection.decrement(key, offset)
+    end
+
     def connection
       @connection ||= Taj::Connection.new(@servers)
     end
diff --git a/test/unit/client_inc_dec_test.rb b/test/unit/client_inc_dec_test.rb
new file mode 100644
index 0000000..a19f48f
--- /dev/null
+++ b/test/unit/client_inc_dec_test.rb
@@ -0,0 +1,47 @@
+require 'test_helper'
+
+class ClientIncDecTest < BaseTest
+
+  def test_increment_simple
+    cache.set key, "10", raw: true
+    assert_equal 11, cache.increment(key)
+  end
+
+#  def test_increment_binary
+#    @binary_protocol_cache.set key, "10", 0, false
+#    assert_equal 11, @binary_protocol_cache.increment(key)
+#  end
+
+  def test_increment_offset
+    cache.set key, "10", raw: true
+    assert_equal 15, cache.increment(key, 5)
+  end
+
+  def test_missing_increment
+    assert_equal(-1, cache.increment(key))
+  end
+
+  def test_decrement_simple
+    cache.set key, "10", raw: true
+    assert_equal 9, cache.decrement(key)
+  end
+
+#  def test_decrement_binary
+#    @binary_protocol_cache.set key, "10", 0, false
+#    assert_equal 9, @binary_protocol_cache.decrement(key)
+#  end
+
+  def test_decrement_offset
+    cache.set key, "10", raw: true
+    assert_equal 5, cache.decrement(key, 5)
+  end
+
+  def test_decrement_with_negative
+    cache.set key, "10", raw: true
+    assert_equal 0, cache.decrement(key, 15)
+  end
+
+  def test_missing_decrement
+    assert_equal(-1, cache.decrement(key))
+  end
+end
diff --git a/test/unit/memcached_test.rb b/test/unit/memcached_test.rb
index 03772af..34e1521 100644
--- a/test/unit/memcached_test.rb
+++ b/test/unit/memcached_test.rb
@@ -60,52 +60,6 @@ class MemcachedTest # TODO
     @marshalled_value = Marshal.dump(@value)
   end
 
-  # Increment and decrement
-
-  def test_increment
-    @cache.set key, "10", 0, false
-    assert_equal 11, @cache.increment(key)
-  end
-
-  def test_increment_binary
-    @binary_protocol_cache.set key, "10", 0, false
-    assert_equal 11, @binary_protocol_cache.increment(key)
-  end
-
-  def test_increment_offset
-    @cache.set key, "10", 0, false
-    assert_equal 15, @cache.increment(key, 5)
-  end
-
-  def test_missing_increment
-    @cache.delete key rescue nil
-    assert_raise(Memcached::NotFound) do
-      @cache.increment key
-    end
-  end
-
-  def test_decrement
-    @cache.set key, "10", 0, false
-    assert_equal 9, @cache.decrement(key)
-  end
-
-  def test_decrement_binary
-    @binary_protocol_cache.set key, "10", 0, false
-    assert_equal 9, @binary_protocol_cache.decrement(key)
-  end
-
-  def test_decrement_offset
-    @cache.set key, "10", 0, false
-    assert_equal 5, @cache.decrement(key, 5)
-  end
-
-  def test_missing_decrement
-    @cache.delete key rescue nil
-    assert_raise(Memcached::NotFound) do
-      @cache.decrement key
-    end
-  end
-
   # Exist
 
   def test_missing_exist