He has been a visiting professor and research fellow in Princeton, Oxford, Dartmouth College, Barcelona, Rio de Janeiro, Tokyo, Auckland, the Harry Ransom Center of U. Texas, the National Autonomous University of Mexico, and other institutions.

[citation needed] Historian Paul Vanderwood asserted, “John Mraz is considered one of the history profession’s most astute students of visual culture”.

[1] Mraz’s books have focused largely on analyzing photographs taken in Mexico, and historian Jurgen Buchenau wrote that he is “widely considered the preeminent expert on the history of Mexican photography".

[3] His first monograph, Nacho López, was said to “answer virtually all of the obvious (but difficult) questions that usually go not only frustratingly unanswered but unasked in photographic histories".

[5] That book was described by Rubén Gallo, Director of Latin American Studies at Princeton University, as “the definitive history of Mexican photography...brilliantly researched, passionately argued, and beautifully written;” on the back cover of another book by Mraz, Gallo affirmed “John Mraz is undoubtedly the world expert on Mexican photography”.

One reviewer said of the productions on Nicaragua and the Mexican railroad workers, “Historians can learn a lot from these films, and they can be viewed with admiration for a colleague who with little budget but with much ingenuity is ‘writing’ history through a medium which is generally appreciated but less well understood”.