The recently discovered natural product class of the tubulysins show a very high cytotoxic activity against in vitro and in vivo tumour models, especially against resistant tumour cell lines. Many representatives of these natural products are several orders of magnitude more potent than other marketed chemotherapeutics. Based on the SAR of the tubulysins this class allows for many chemical conjugation and targeting strategies which offer several different development and business opportunities. They are very good suited for any kind of conjugation to polymers or biomolecules such as e.g. antibodies or proteins. But also for conjugation approaches with RNAi’s, TCR’s, aptamers, nanobodies etc. tubulysins should be considered.