In this paper, we propose an engineering approach to software engineering called "Unified Software Method" (USM). The goal pursued through this work in progress is to offer complete traceability between software requirements and the resulting software application for any kind of application and as a result, establish accountability of a practitioner's work. This paper presents an introduction to USM and focuses mainly on how USM can apply traceability to maintain synchronization between a software application and the relevant documents such as requirements, architecture, design, code, test, and executable.