Every product or service (system) needs a rationale for acquisition, development, modification, operational environment, and usage. Requirements provide the definition and form the basis of the need for the product or service. As systems complexity increases, a greater attention is required to understand customer needs early in the development lifecycle. Requirements analysis, a.k.a. requirements engineering, is the process of identifying and validating the customer needs and transforming those needs into system requirements. MBSE and requirements analysis together provide the tools and workflow to examine, evaluate, and translate customer need statements into a requirement baseline and model framework for system definition, design, and development. This presentation describes how requirements baseline is enhanced by applying the rigorous and disciplined approach that MBSE brings to bear in the requirement analysis process.