In-situ hot deformation has been carried out in a field emission gun SEM equipped with an EBSD system to study dynamic subgrain growth and substructural evolution in a single-phase aluminium alloy. {110}<001> oriented single crystals of the alloy were deformed in a channel-die in plane strain compression at 300 C at a strain rate of 10(-1)s(-1) before in-situ straining in tension at strain rates of 10(-4) to 10(-3)s(-1) and at temperatures from 300 to 350 degreesC. Significant dynamic subgrain growth was found to occur during a transient period during which the compressed microstructure evolved towards a steady state corresponding to the strain rate applied. The mechanisms of dynamic recovery are seen to involve both sub-boundary migration and subgrain dissolution and formation.