In 1990 The California Academic Press published its first reasoning skills test, and, in 1992, its first critical thinking disposition inventory. Since that time research has continued on the development of a broader array of reasoning assessment tools and on expanding what is known about critical thinking, problem-solving, and decision-making. The focus of this research has been on integrating humanistic and scientific approaches with the expressed purpose of achieving practical gains. The aim is to assist people in becoming better thinkers by knowing how thinking works, how improvements in thinking can be learned, how mistakes in thinking can be identified and avoided, and how one can use meta-cognition as well as objective assessment information to improve one's own thinking.

First as The California Academic Press and now as Insight Assessment, the sale of reasoning tests lead naturally to consulting activity, to the custom design of assessment tools for clients with particular evaluation objectives, and to the development of support services, such as test scoring and analysis, to provide cost-effective, high quality, and technically sound services and products to an ever expanding client base. Having been translated into many languages, today Insight Assessment's tests are used throughout the world.