Over the last decade, the Intelligent Computer Tutoring Group (ICTG) has implemented many successful constraint-based Intelligent Tutoring Systems (ITSs) in a variety of instructional domains. Our tutors have proven their effectiveness not only in controlled lab studies but also in real classrooms, and some of them have been commercialized. Although constraint-based tutors seem easier to develop in comparison to other existing ITS methodologies, they still require substantial expertise in Artificial Intelligence (AI) and programming. Our initial approach to making the development easier was WETAS (Web-Enabled Tutor Authoring System), an authoring shell that provided all the necessary functionality for ITSs but still required domain models to be developed manually. This paper presents ASPIRE (Authoring Software Platform for Intelligent Resources in Education), a complete authoring and deployment environment for constraint-based ITSs. ASPIRE consists of the authoring server (ASPIRE-Author), which enables domain experts to easily develop new constraint-based tutors, and a tutoring server (ASPIRE-Tutor), which deploys the developed systems. ASPIRE-Author supports the authoring of the domain model, in which the author is required to provide a high-level description of the domain, as well as examples of problems and their solutions. From this information, ASPIRE generates the domain model automatically. We discuss the authoring process and illustrate it using the development process of CIT, an ITS that teaches capital investment decision making. We also discuss a preliminary study of ASPIRE, and some of the ITSs being developed in it. (Contains 18 figures, 2 footnotes, and 3 tables.)