IP Multimedia Subsystem (IMS) is part of the 3G mobile network that allows deployment and blending of multimedia services for its users. This subsystem was specified as a standard by the standardization organizations such as the 3rd Generation Partnership Project (3GPP), Internet Engineering Task Force (IETF). These organizations also include the standard for the services as well as all other components that are part of the system. IMS is aimed to provide multimedia services to all generations of networks and devices. Service compositions allow the users to get the blended services to subscribe to with IMS. But all compositions do not always lead to desirable outcomes leading to feature interactions. The network operators use their monolithic or man-in-the-middle approach to handle these interaction issues which are often constrained and expensive. To address the issue of feature interaction, the 3GPP proposed to place an entity known as the Service Capabilities Interaction Manager (SCIM) between the S-CSCF and the Application Servers(ASes). With no specifications of this entity provided, many proposals for the specifications came from the research community and SCIM products are developed by the telecom vendors. Due to no standardization, these products are vastly different from one another and often expensive which has made many telecom operators reluctant to include it in their network. This thesis investigates the standards and research available on the topic of feature interaction along with the SCIM products to understand the advantages and limitations. The information from the investigations are then utilized to make proposals for both functional and non-functional requirements that a SCIM should hold. Furthermore, two existing SCIM products are evaluated using the requirement suggestions.