When Allison Moorer released her last album, 2004’s The Duel, she said goodbye to a large part of her past. Working with a new band on a new label (an indie, no less) and incorporating a new sound, Moorer forged a new beginning, opting to write songs that were decidedly more rock than country.

What was most striking about the album, however, was the lyrical content, which violated every unwritten rule in country music by questioning God, criticizing the president, and exposing the folly of America’s military ambitions. In other words, the good ol’ gal who had diligently mined the traditions of country had taken a turn towards the left, which makes life very hard in the evangelical-driven country mainstream.

Overall, The Definitive Collection is an essential purchase for fans of country, alt-country, folk, and roots rock. Moorer is still relatively unknown—and almost certain to never “break”—but she’s already created a legacy that places her within sight of country’s pantheon of legends. By avoiding the short-term benefits of cashing in, she’s ensured her spot as an influential artist, the type that’s appreciated more by successive generations. Where Moorer’s career goes from here is anybody’s guess; Steve Earle is producing her next album, and we’ve already seen what Moorer is capable of when she takes off the gloves. Though her first four albums are undeniably great, they might be a mere prelude to something legendary.