Until today there are numerous objects in the storage of the Ethnologisches Museum Berlin which have been appropriated by the colonial power of former German East Africa between 1885 and 1918. The project 'Humboldt Lab Tanzania' joins Tanzanian and German researchers, curators, and artists who critically discuss chosen artefacts. Since relocation of the Ethnologisches Museum to Humboldt Forum public awareness for collections from former German colonies and objects of often problematic provenance has risen. Thus, participants from Germany and Tanzania attempt new ethnological, historical and museological approaches to display the entangled colonial History. Taken into account is the semantic change, which the objects underwent over time, as well as the issue of proper dealing with ethnological collections from colonial contexts. In which way and where can these sensitive objects and their histories be (re)presented in theory and practice of museums?