The article examines to the problems of knowledge economy development governance at a regional level. International experience demonstrates successful examples of knowledge economy development in different regions and cities. However, the process is controversial, and there are also cases that reveal an absence of progress in the development of the knowledge economy. The goal of our study is to review basic models of knowledge economy development, analyze their evolution and reveal the dependency of knowledge economy development on the methods and tools of its assessment. The study that we have performed is based upon a series of interviews with managers and regional authorities. It demonstrates that the assessment of knowledge economy's contribution to a region's key performance indicators is the major problem for regional policymakers. The above indicators include gross regional product, labour productivity, the level of salaries and the unemployment rate. Apparently, the issue of assessment of the knowledge economy has a fundamental nature.