Future military aircraft must achieve higher reliability to improve operational readiness, increase sortie rate, improve survivability, and reduce maintenance and operational costs. One way to accomplish this is to utilize new technologies and approaches to integrate the functions of the utility subsystems. Utility subsystem failures can lead to serious damage or aircraft loss (e.g., gear locked up).During Phase 1 of the Air Force Study Contract SUIT (SUbsystem Integration Technology), Rock well identified the significant aircraft improvements attainable through the collaborative design, integration, and control of the utility subsystems. A systematic integrated design methodology was implemented during Phase 1 to identify and the integrate common subsystem functions and common parameters. The significance of this methodology is that it formalizes and quantifies the assessment process in such a way that it provides objective results and a foundation for subsystem integration recommendations. From this study approach, a new integrated utility subsystem suite was generated that included important key technology advantages, six critical functions, and six major subsystems. The following functional integration technologies make up the core integrated baseline suite: (1) integrated closed environmental control, (2) integrated hydraulic power, (3) shared electrical power-vehicle power management, (4) integrated secondary power, (5) integrated fuel and thermal management, and (6) integrated utility subsystem control.This paper gives a overview of the integration methodology utilized to assess the subsystem design process and describes the integration technologies that were defined during SUIT Phase I.