Most members of the Montana Archaeological Association tended to belong to the Montana Archaeological Society as well, but the MAA being entirely made up of professional archaeologists, they were able to concentrate their efforts onto more specialized areas of interest. Some of the major causes undertaken by the MAA include the Native American Free Exercise of Religion Act, the Burial Bill Act and the Montana Antiquities Act among others. The MAA worked diligently to sponsor laws and to create guidelines for the ethical issues relating to archaeological work. The group worked closely with the Montana State Historic Preservation Office (SHPO), and in 1991 MAA and SHPO co-sponsored the first annual Archaeology Week in the state of Montana. This recurring event quickly became an important staple in the promotion of public awareness and education relating to local archaeology.

The Montana Archaeological Association found it increasingly difficult to continue its lobbying activities and sponsorship of the Archaeology Week program while relying strictly on volunteers. In 1996, the MAA, having never officially incorporated itself as an organization under Montana state law, elected to dissolve and to delegate all of its interests and activities to the MAS. Since the membership of both groups overlapped, the transition was smooth and the Montana Archaeological Society assumed all responsibility related to the sponsorship of Archaeology Week, as well as a more pronounced role in the political lobbying that had been such an important facet of the MAA. The two groups officially merged together after members approved the decision at their annual spring meetings in 1996.