Enterprise architecture management (EAM) is expected to contribute to, e.g., strategic planning and business-IT-alignment by capturing the essential structures of an enterprise. Enterprise architecture principles (EAPs) are among the subjects in EAM research that have received increasing attention during the last years, but still are not fully covered regarding their characteristics and their development and use in practice. The aim of this paper is to contribute to the EAM field by investigating the nature of EAPs and by proposing and validating a development process for EAPs. The main contributions of the paper are (a) an analysis of the characteristics of EAPs, (b) an initial development process for EAPs, and (c) the results of expert interviews for validating this process.