Purpose - Sustainability in Corporate Real Estate has lately become a concurrent part of almost every enterprise. However the extent of activity may extremely differ in various industries. Sustainable Real Estate Practices have been broadly analyzed in the recent studies, but the holistic approach to the issue is missing. The purpose of this paper is to summarize and systematize the current activities and propose a generic Sustainability Maturity Model in Corporate Real Estate. Methodology - The theoretical model is created based on findings from literature review. It consists of Sustainable Real Estate Practices which are divided into 6 dimensions: resources, processes, governance, communication, finance and strategy. Throughout the practices the role of Real Estate at each of the five Sustainability Maturity levels is explained. It is assumed that the highest proficiency of Sustainability is mastered by the most sustainable companies and enterprises. Therefore, the reliability of the model is tested in interview sessions with the field leaders in Finland. The results are analyzed using qualitative research methods.Findings - Over 10 interviews with Finnish companies were conducted to find out what Sustainable Practices are possessed at different maturity levels. Based on these results, the theoretical model is tested and developed further and as a result generic Sustainability Maturity Model for Corporate Real Estate is suggested. Originality/value - This model provides a holistic and systematic approach to the present Sustainable Practices and demonstrates how Corporate Real Estate contributes to Company’s Sustainability.