<p>Although motor deficits in developmental coordination disorder (DCD) are well documented, the underlying neurological alterations remain poorly understood. While some studies report reduced grey matter (GM) volume and altered white matter (WM) organisation, others show contradictory results or found no differences at all. These studies focus exclusively on paediatric populations and commonly employ diffusion tensor imaging (DTI). This technique is limited in distinguishing crossing fibres, which compromises the reliability of its findings. Therefore, we used the state-of-the-art fixel-based analysis (FBA) technique, providing a more precise measurement that accounts for crossing fibres. Sixteen adults with DCD and thirteen typically developing (TD) peers (18-35y) underwent comprehensive motor assessment (MABC-2) and T1- and diffusion-weighted imaging (DWI) MRI scans. GM volume was examined in motor-related regions, including the motor cortex, basal ganglia, cerebellum, and dorsolateral prefrontal cortex. WM organization was analysed in key motor tracts such as the corticospinal tract (CST), cerebellar peduncles, and superior longitudinal fasciculus (SLF). No significant differences in GM volume or WM organization were found between adults with DCD and TD controls. Additionally, there was no significant relationship between WM organization and motor performance scores. However, with this relatively small sample, small or moderate effects remain undetected. Furthermore, according to Bayesian analyses the findings only provide anecdotal support for the absence of group differences, except for the left middle cerebellar peduncle (MCP), where moderate evidence supported the null hypothesis. Future studies with larger samples are needed to confirm these conclusions.</p>