Visual Studio 2005 Extensions for SharePoint Workflow

Wokflow is integrated with MOSS(Microsoft Office SharePint Server 2007), The workflow integration with MOSS 2007 can be created in the following two ways.

Out Of the BOX functionality WorkFlow in SharePoint Designer 2007
Creating Custom Workflow in Visual Studio 2005 using SharePoint workflow Extensions

Download and install Visual Studio 2005 Extensions for SharePoint Workflow

Thanks & Regards,
Udayakumar Ethirajulu