First let's take a look at MPSS. IBM's MPSS is a solution enablement framework, intended to accelerate and facilitate the creation of manufacturing solutions for the automotive industry that integrates the factory floor with suppliers and other systems in the company(such as order management, inventory management and quality systems.) MPSS does this by providing a framework, templates, and tools for integration of existing applications and creation of new applications based on a Services Oriented Architecture (SOA).
What value does ISM add to MPSS? ISM provides the ability to define and automate key processes. The Change and Configuration Database(CCMDB), for example, provides the ability to discover all configuration items and their relationships, a platform for designing and implementing workflows, and best practice processes for change and configuration management. Another example is the The Tivoli Availability Process Manager, that can add best practices workflows for availability management, incident management, and problem management which are key to managing the performance, reliability and security for manufacturing based solutions.