This research paper builds on a case study performed at a Norwegian company that deals with a large number of small Engineer-To-Order (ETO) projects. Recently, the company started an improvement process pursuing lean principles. One of the initiatives taken by the company is to improve the present planning process, which lacks a whole-project view that can give managers a better decision ground. Two important departments, engineering and production, develop project plans that are based on their own specific approaches and with little collaboration between the departments. This paper presents the preliminary results of implementation of Lean Project Planning (LPP), a planning tool developed within shipbuilding industry, a typical ETO environment.