There are 2 books by Erik D. J. O'Brien on BookOrb. A strong starting point is Drums of Doom (1987). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has Erik D. J. O'Brien written?
BookOrb lists 2 books by Erik D. J. O'Brien.
Where should I start with Erik D. J. O'Brien?
A good starting point is Drums of Doom (1987).
What is the Erik D. J. O'Brien books in order list?
In publication order: 1. Drums of Doom (1987), 2. Last Admiral (2016).