Information modeling is the cornerstone of information systems analysis and design. Information models, the products of information modeling, not only provide the abstractions required to facilitate communication between the analysts and end-users, but they also provide a formal basis for developing tools and techniques used in information systems development. The process of designing, constructing, and adapting information modeling methods for information systems development is known as method engineering. Despite the pivotal role of modeling methods in successful information systems development, most modeling methods are designed based on common sense and intuition of the method designers with little or no theoretical foundation or empirical evidence. Systematic scientific approach is missing! This chapter proposes the use of cognitive psychology as a reference discipline for information modeling and method engineering. Theories in cognitive psychology are reviewed in this chapter and their application to information modeling and method engineering is discussed.