Abstract BACKGROUND Cerebral bypass remains important for the treatment of complex cerebral aneurysms including dissecting, giant, and fusiform aneurysms not amenable to endovascular treatment or simple clip ligation. For such aneurysms involving the anterior communicating artery complex or its branches, distal anterior cerebral artery (ACA) A3-A3 side-to-side bypass represents a valuable treatment option. Distal ACA in situ anastomosis is recognized to be technically demanding mainly due to the relative depth and narrowness of the interhemispheric surgical corridor and type of anastomosis. OBJECTIVE To demonstrate technical nuances of A3-A3 side-to-side in situ bypass surgery through case illustrations and operative videos. METHODS Elements of the procedure relating to positioning, approach, and anastomosis which have evolved in the operative technique of the senior author were collated based on review of clinical case material, imaging and video recordings of ACA aneurysms treated with side-to-side in situ A3-A3 bypass procedure. Technical elements were contrasted with relevant literature. RESULTS Nuances relative to patient positioning, selection of craniotomy variants, adjunctive intraoperative tools and microsurgical nuances of the side-to-side bypass procedure are reviewed. Three illustrative operative video cases, along with illustrations, are provided to complement the description of the nuances. CONCLUSION In the light of the inherent technical difficulty, as well as the rather limited case volumes, the technical tips provided may contribute to bringing additional refinement and simplicity to the A3-A3 bypass procedure.