The main purpose of this study is to analyze de lege lata the tax treatment applicable to CISs and trusts in both Swiss domestic and international tax law under the provisions of the DTCs currently in place in Switzerland, as well as the OECD’s standards. The topic is analyzed from a critical angle and its conclusions include recommendations and a de lege ferenda evaluation aimed at ensuring CISs’ and trusts’ access to DTC benefits. • Important and up-to-date analysis for trusts and collective investments schemes • In-depth study of Swiss and international tax law • Pragmatic, critical and solution-oriented approach