Binding Time Analysis (BTA, BT-analysis) is an essential part of the Partial Evaluation (PE) technique of program specialization. The results of BT-analysis are used for decorating a program to be specialized with annotations, which are used later by the residual program generator. The specializer CILPE deals with programs written in SOOL, a simple Stack Object-Oriented Language. The paper present the approach to BT-analysis taken in CILPE. The annotations added to a SOOL program must satisfy certain requirements, which are formulated as a set of inference rules. The BT-analyzer in CILPE complies with these rules.