This research proposes an Engaging User Experience (ENUX) framework which caters for the influential User Experience (UX) and User Engagement (UE) dimensions for a MAR system. The ENUX framework extends on the UX and UE theoretical groundings, the multimodal and multisensory techniques and performance metrics to effectively enhance the UX and UE in MAR systems. Designers and developers in the MAR field have focused on providing a usable system rather than concentrating on a user-centric system that may lead to an enhanced UX and UE. The recommendations from the ENUX framework adopt a user-centered perspective to ensure a high-quality MAR experience in various application areas, and therefore can demonstrate the following: point of engagement, period of engagement, maximum engagement and re-engagement. An initial MAR prototype for a cultural heritage site has been developed using the instrumental, cognitive and sensory dimensions from the ENUX framework. A field study of sixty-six users has evaluated the MAR prototype to carry out an impact analysis of the contribution of the ENUX framework. The findings have confirmed that the partial development of the ENUX framework have significantly improved the UX and UE in the MAR prototype and is a promising start to implement the overall ENUX framework. The framework lays a solid foundation for the assessment of the UX and UE factors in MAR systems, which has the potential to assist the MAR system developers to identify and improve the most UX and UE influential factors in their systems.