Controlling the weight of a vessel over the design and engineering life cycle is critical, but is an ongoing challenge for shipbuilders. Excellent tools exist for both weight estimation and control and design and engineering; however the area where these two meet is often filled with Microsoft Excel spreadsheets or databases developed in house by individual shipyards. These approaches leave much to be desired. This paper will explore the implementation and benefits gained by integrating existing design and engineering tools with existing weight control applications.