In this paper we discuss the problem of combining advanced instructional design with state-of-the art e-learning technology into an effective blended learning environment. Advanced instructional design refers to modern approaches towards training: task oriented instruction, competency-based learning, and learning by doing. This implies a mix of different instructional methods to achieve optimal transfer of training (effectiveness driven). State-of-the art e-learning technology refers to modern approaches towards training delivery: distributed learning and virtual environments. This implies a mix of different delivery mechanisms and standardized learning content to achieve optimal flexibility and reusability (efficiency driven).

A combination of both aspects is called a blended learning solution. Conventional training methods (e.g. classroom based instruction) are used when they are appropriate or practical. Digital training methods (e.g. individual or collaborative learning in virtual environments) are used where distribution or individualism is in order and the educational turnover will not be negatively influenced. A major problem is that combining different instructional methods and delivery mechanisms causes an increased complexity in the already complex process of specifying, developing and implementing learning environments. Such an effort requires a holistic perspective on the development process. However, currently, not much concrete guidelines, Instructional Systems Development (ISD) models, or best practices are available for blended learning. Particular the transfer between Instructional Design and production of learning content is often problematic.

In this paper, we discuss our experiences with Blended Learning projects in the Royal Netherlands Air Force (RNLAF) and in creating a systematic, integral approach towards specifying and developing blended learning environments. This discussion is based upon a heuristic model of a blended learning environment, the Four Quadrant model. We seek to connect to best practices in the IT industry (like using the object orientation as a basis for our design models) and conventional Instructional Systems Development (ISD) techniques as a fundament for our systematic, integral approach. Important elements of the systematic, integral development approach are a) specifying criteria in each phase, b) evaluation of intermediate products by means of these criteria at the end of each phase, c) template-based specification and development, and d) case-based reflections on critical events.