Street and Smith was the original publisher of the Doc Savage Magazine. The series started with the March, 1933 issue and ran for 181 issues, ending in July, 1949, becoming one of the longest running pulp heroes.
Bantam Books took on reprinting the series in the '60s, but did not publish the stories in the same order that they were originally published. Bantam published the series as individual books books before switching to double novels, then finishing the series with "omnibus" volumes of some four or five stories.
Nostalgia Ventures is the latest publisher to take on Doc Savage, utilizing the original covers with the books, along with alternate Bantam Books edition covers. These volumes also contain articles on Doc Savage, Lester Dent and the writing of the series.