For anyone who is more interested in the plot of The Tesserene Imperative (Book Two) than that of The Mars Imperative (Book One), or who doesn't want to get "hooked" on another never-ending book series, there is something you should know. These two books are only loosely connected. Yes, they're set in the same fictional universe, but the stories take place a decade apart, with different characters. And where The Mars Imperative is set in our solar system, The Tesserene Imperative takes place almost entirely in deep space.
For comparisons, think of Saberhagen's Berserker series (Berserker Throne, etc.) or McCaffrey's Brainship series (The Ship Who Sang, etc.), each with different characters and stories, with only slight overlap between them.
Therefore, either book could be read alone, or in either order, without affecting your enjoyment of them. I do, however, have plans for a third book to follow The Tesserene Imperative. I thought it would be fun to have an adventure involving characters from both books working together. (The working title is The Galactic Imperative.)
There is also the possibility some day of a prequel (Book 0?) to The Mars Imperative, set two decades earlier and involving two of the secondary characters from The Mars Imperative at an earlier point in their careers, but that's speculative at best. I have no plans for any other books in the series, so you don't have to worry about The Imperative Chronicles turning into a Game of Thrones and having to wait a decade for me to finish the series. Except for Book 3 (which would benefit from reading Books One and Two first), the others could be read in any order--or skipped entirely. (You wouldn't do that, though, would you???)