Trigger factor (TF) is a highly conserved bacterial chaperone that binds to the exit of the ribosomal tunnel through which newly synthesised polypeptide chains emerge and interact with TF during co-translational folding. While TF binds to the ribosome in a 1:1 stoichiometry, free TF tends to dimerise through the ribosome binding domain, while the chaperone domain and the peptidylprolyl isomerase domain may in some ways contribute to the homo-dimerisation. In this talk, I shall discuss our endeavour to combine nuclear magnetic resonance (NMR) spectroscopy, small angle X-ray scattering (SAXS) and electron spin resonance (ESR) spectroscopy to explore how TF dimerises in solution at an apparent molecular weight of 100 kDa. Our results indicate that, while structurally polymorphic, TF exhibits a few preferential modes of dimerisation, which are distinct from the reported crystal structures and may be associated with its promiscuous chaperone activity.