Resolution by Robert B Parker

The second in a trilogy, Parker has Hitch working as a lookout in a saloon and a protector of ladies who work there, not always to the liking of his boss, Amos Wolfson. Gun slinger and stoic, things aren't the way they ought to be and when Virgil Cole, arrives, the plot thickens. A great read. If you haven't read Appaloosa or Brimstone, the stories dovetail nicely and you might want to read them in order.