McAlvany attended the University of Texas. In 1972, McAlvany founded International Collectors Associates (ICA), headquartered in Durango, Colorado. The firm is described as a "securities, precious metals brokerage, insurance and consultation firm serving clients in over 20 countries." In 1976 McAlvany began publishing the McAlvany Intelligence Advisor, a monthly newsletter that analyzes economic, political, and financial issues, globally. In recent years he has also produced a monthly podcast on economic and "hard money" investing.

He has been a lecturer at Christian, political, monetary and investment conferences "in Western Europe, Africa, Australia, the Middle East, Hong Kong, Singapore, as well as all over the North American continent and Latin America."

He serves on the board of The Conservative Caucus, is a member of the Council for National Policy, is chairman of the Council on Southern Africa, was "a founder of the Industry Council on Tangible Assets (ICTA), and one of the founding directors of the fellowship of Christian Financial Advisors."

He was formerly the editor of The African Intelligence Digest.

McAlvany co-authored the nonfiction books Steeling the Mind of America (1995) and Earth's Final Days (1996).

McAlvany gained some notoriety for his prediction of a possible Y2K catastrophe, before 2000. In 1999, McAlvany self-published the book Y2K Tidal Wave: Year 2000 Economic Survival. Like survivalist authors Joel Skousen and James Wesley Rawles, and economists Dr. Gary North, Ed Yourdon and Ed Yardeni, and many others, McAlvany suggested that a Y2K date-rollover failure of the global Information Technology (IT) infrastructure might precipitate severe disruption and perhaps even an economic collapse.In the event there were no significant problems (dispute continues on whether because of remediation efforts or because the danger had been overstated), but McAlvany later described Y2K as "a close one."