The performance of concrete bridge decks was identified as the top performance issue within the Federal Highway Administration’ (FHWA’s) Long Term Bridge Performance (LTBP) Program. To enable accurate, rapid and economical condition assessment of decks on a large number of bridges, the system named RABIT (Robotics Assisted Bridge Inspection Tool) was developed. The system concentrates on the characterization of internal deterioration and damage, in particular three most common deterioration types: rebar corrosion, delamination, and concrete degradation. For that purpose, the RABIT implements four nondestructive evaluation (NDE) technologies: electrical resistivity (ER), impact echo (IE), ultrasonic surface waves (USW) and ground-penetrating radar (GPR). Multiple NDE probes or large sensor arrays significantly improve the spatial resolution of the results. In addition, high resolution cameras image the surface of the deck for crack mapping and documentation of previous repairs. The paper provides an overview of the RABIT system and describes how the data collected by the system are being used in the development of more realistic deterioration and predictive models for bridge decks.