This study uses new information acquired from field mapping, mineral exploration boreholes, and seismic reflection profiles to constrain the structural geology, deformation mechanisms, and timing of the Penobsquis salt structure. This information is used to place the development of the salt structure into the context of the tectonic evolution of the Moncton Basin. The Penobsquis salt structure is an elongate salt wall separated from underlying rocks by a mylonitic detachment horizon. It may be divided into two segments: a southwestern asymmetric, southeast-verging structure and a northeastern strongly asymmetric to overturned, southeast-verging structure associated with the Penobsquis fault. An initial low-amplitude salt anticline formed during deposition of the Mabou Group (Serpukhovian time). The salt anticline was modified into a high-amplitude salt wall after deposition of Cumberland Group sediments (early Bashkirian or later). The sense of asymmetry of the Penobsquis salt structure, the presence of thrust faults within the structure, the spatial association of the structure with a major reverse fault in the salt cover, and the temporal association of salt movement and compressional tectonic events suggest that the salt structure developed in response to tectonic contraction during inversion of the Moncton Basin.