Despite the increasing investment and interest in drug development, the amount of time and resources needed to develop a new drug continues to rise. Biomarkers are an important tool with the potential to decrease the time, cost, and failure rate of drug development. Given the role of biomarkers in drug development, it is important to understand how biomarkers are identified, developed, and validated, so that the costs of these activities can be assessed. Currently, there is limited published information and cost data describing the financial and other resources required for biomarker development that examines discrete phases of development and differences between biomarkers. The objective of this project was to develop a framework for estimating the cost of biomarker development and validation for use in drug development. To achieve this objective, the project included an environmental scan, expert consultations, case studies and development of a framework for understanding the biomarker development and validation process, activities that drive the process, and factors that drive cost.