Critical Insights, a Portland firm that has provided market research, analysis and polling services since 1992, is being acquired by a southern Maine competitor.

Digital Research Inc. of Kennebunk announced the acquisition of Critical insights in a Monday press release. Terms of the deal were not disclosed.

“Both DRI and Critical Insights were poised for growth, having exhibited strong performance for over two decades, and more recently despite a period of economic stagnation,” said MaryEllen FitzGerald, president of Critical Insights, in the release. “As we both looked to expand our businesses, it made sense to merge, rather than to compete. We are delighted with the outcome and potential for the new entity.”

DRI, which uses innovative data collection techniques, is known for its analysis in travel and tourism markets, as well as in consumer goods. Critical Insights specializes in health care, public policy, advertising and regulated industry sectors such as banking and utilities. It also provides public opinion polling for local and national media.

The complementary nature of the firms’ areas of expertise is what drove merger discussions, said FitzGerald. Bob Domine, president and CEO of DRI, called the merger a “powerhouse of capability” in the release.

Critical Insights will become a division of DRI, with FitzGerald remaining as its president.

Both companies intend to maintain their existing office locations and hire additional staff.