The municipality consists of the following former municipalities, now sub-municipalities: Rixensart proper, Rosières (Rozieren), and Genval. Genval-les-Bains is a local beauty spot, a 100-year old lake with a fountain, and framed by trees, houses and restaurants. Rixensart is home to the beautiful private-owned Chateau de Rixensart.
Rixensart is served by two railway stations (at Rixensart and at Genval), connecting it with Brussels to the north and Louvain-la-Neuve to the south. The new arrival of the Brussels RER, will improve both train stations and upgrade the number of trains going from Brussels to Namur to 4 per hour. This will also bring more people to the municipality to live. The commune is now classified as a commuter town due to its proximity to Brussels, the RER and the E411 Motorway.