Accurate shape, size and morphology characterisation of drug delivery systems is crucial for understanding their behaviour, especially for dynamic self-assembled systems. This will help to define their potential as drug delivery vehicles. As an example, morphology and shape can affect cargo loading and cellular uptake. Conventional DLS and TEM can give an indication of nanostructure size, polydispersity and shape, but complementary techniques are needed to decipher the internal morphology of self-assembled particles. SANS allows more detailed structural information to be acquired in an artefact-free manner to obtain bulk properties such as morphology and polydispersity. Cryo-TEM is a useful tool for imaging self-assembled nanostructures to obtain a snapshot in their native hydrated state. Often, the drying step in the sample preparation procedure needed for negative stain TEM introduces drying artefacts, which may prevent accurate morphology determination. A combination of SANS and cryo-TEM is often used when characterising block copolymer assemblies in solution, e.g. when studying vesicle shape transformations at the nanoscale. We used these two techniques to further analyse the self-assembly process by first studying the copolymers before ('coil' state) and after self-assembly ('globule' state) (Figure ). The data obtained for 5a4 suggests that this block copolymer has fully swollen chains in good solvent conditions at 25 °C (below the LCST) in agreement with literature on similar copolymers. A power law exponent of 1.96 ± 0.01 block copolymer 5c1 is explained by the presence of polymer chains in theta conditions with equally favoured polymer-polymer and polymer-solvent interactions.