This paper describes the Microsoft Interactive Television (MITV) system. An overview of the different components of the system is presented. The development process is described. Finally, experiences and lessons learned from the system are presented. The system is designed to be able to provide traditional television service, video-on-demand service, and custom interactive applications, such as interactive shopping services, to subscriber bases scaling from a few hundred subscribers up through major metropolitan areas. An early version of the system was deployed in a trial of 100 subscribers in the Redmond, Washington area with TCI and Viacom from April, 1995 to early 1997 using PCs to emulate set-top boxes; a trial of 298 subscribers was deployed from March 1996 to April 1997 by NTT and NEC in Yokosuka, Japan using client-premises set-top boxes. From initial conception in early 1993 thorough the trial deployments, an eventual staff of over 200 people evolved the design and implementation of the system to meet changing requirements under tight deadlines. The team delivered a working system on time (a rare occurrence in the software industry!). This paper will describe both the eventual architecture of the MITV system and some of the compromises made and lessons learned in building and deploying this substantial commercial software system.