Dolphin Discovery runs one of its flagship facilities at Puerto Aventuras, in a sheltered lagoon alongside the marina. Programmes range from a shallow-water interaction — you stand chest-deep and the dolphins come to you — to a full swim where they tow you across the lagoon by the dorsal fin.
It is a professional, well-run operation and genuinely popular with families. The dolphins are Atlantic bottlenose, and the handlers are trained guides who take the interaction seriously. If your trip to the Riviera Maya is going to include a dolphin encounter, the Puerto Aventuras facility is one of the better options — it is less crowded than the Cancún sites and the lagoon setting is more natural-feeling than the tank-based alternatives.
Book in advance; the swim programmes in particular sell out days ahead during high season. Prices vary by programme; the full swim is the most expensive.