The dissertation titled “Architect Rudolf Tӧnnies – his life and works“, covers, like the title itself suggest, important facts that influenced his future period of affirmation, establishment and development as architect and artist-cum-designer, such as the facts relating to his family circumstances and predispositions for his future work, but focusing primarily on his creative period in BiH. As the activities of Architect Rudolf Tӧnnies in Croatia were brief and negligible, in Slovenia they were related to the activities the Company Obnova, gradbena družbaz.o.z. Ljubljana, and in Vienna limited only to 11 standardized designs for officers' pavilions, these have only been partially analysed, leaving an opportunity for a future researcher to explore his works outside the borders of BiH. Considering that Sarajevo or BiH is where the Architect made his most significant contribution to the architectural heritage of the Austro-Hungarian period, this paper analyses, describes, valorises and compares all of his finished and unfinished designs, independent and those done in cooperation with the leading architects of the Monarchy. The facts presented here are documented and corroborated by evidence, such as preserved design documents and relevant written materials (data from his personal files, published and unpublished records and exceptionally locally found reference materials). In terms of referencing, three sources were used – information from personal file of Rudolf Tӧnnies, the design documents and written materials from the Archive of BiH (documents relating to the Construction Department of the Royal National Government for BiH, more specifically, the Building Construction Department). In terms of scope, the paper mostly focuses on the projects implemented in Sarajevo as well as those in other towns in BiH, this is followed by his collaborations, then his unimplemented projects and finally other works (such as: scale models, sketches for interior design, awards and recognitions received, etc.)