Lianas affect many aspects of tropical forest dynamics and thus the study of their ecology is critical for a comprehensive understanding of tropical forest ecology. Recently we initiated a complete census of all lianas ≥1 cm diameter in the 50 ha forest dynamics plot on Barro Colorado Island Panama using the census protocol developed by Gerwing et al. [Gerwing J.J. Schnitzer S.A. Burnham R.J. Bongers F. Chave J. DeWalt S.J. Ewango C.E.N. Foster R. Kenfack D. Martinez-Ramos M. Parren M. Parthasarathy N. Perez-Salicrup D.R. Putz F.E. Thomas D.W. 2006. A standard protocol for liana censuses. Biotropica 38 256–261]. This protocol marked an important advance in the study of lianas by providing a standard methodology that can be used for liana censuses worldwide thereby making accurate comparisons among studies possible. During the course of our census however we encountered a number of recurring situations that were critical for accurate and repeatable liana censuses but were not covered in the protocol of Gerwing and colleagues. In this paper we present a supplemental protocol that covers these additional situations. Our supplement combined with the protocol developed by Gerwing et al. provides a more complete set of methods with provisions for situations commonly encountered in liana censuses.