Purpose Ocular development may be disrupted at various stages, leading to a wide range of congenital ocular dysgenesis. Incidence of such defects is estimated to 1-2 in 10.000. They may be isolated or associated with extra-ocular malformations. In addition, psychomotor delay may be present, secondary to the sensory involvement or linked to a cerebral developmental anomaly leading to intellectual disability. Visual outcome, frequency of extra-ocular features and psychomotor delay are still poorly known. Given the rarity of these malformations, available data concern very heterogeneous groups of patients, which make their utility limited in clinical practice. It is thus difficult to anticipate visual and neurologic outcomes when a congenital ocular developmental anomaly is diagnosed. Methods RaDiCo-AC-ŒIL is an observational study launched in May 2017 sponsored by Inserm, relying on the French Rare Diseases healthcare networks SENSGENE and ANDDI-Rare for patients’ enrolment, and supported by patients ‘associations. Patients will have a maximum of three clinical examinations (at time of diagnosis, at 5-7-year-old, and at 9-11-year-old) during which visual, neuro-developmental and quality-of-life data will be collected in addition to the usual clinical data, using REDCap EDC system. It will extend to other EU countries once regulatory requirements will be fulfilled. Results About 800 patients are expected to be enrolled during a recruitment period of 10 years. Conclusions RaDiCo-AC-ŒIL will improve i) our knowledge on the natural history of ocular developmental defects in children ii) the identification of prognostic factors for ocular and neurodevelopmental outcome iii) genetics counselling and iv) the design of optimised management protocols. This project will also pave the way to clinical and basic research in a homogeneous cohort.