Abstract
When introducing product line engineering into an organization there normally have been systems already developed in the domain. There are legacy assets in different forms which should be integrated into the product line. In this paper we describe the role of legacy documents in the product line engineering life cycle and especially for domain analysis. We propose some basic techniques for eliciting knowledge which is relevant to the product line and can increase domain undestanding. Those techniques can be used for the elicitation of commonalities and variabilities from legacy documentations and produce candidates for elements of a domain model which can be proposed to the domain experts during domain analysis.