There has never been a greater appreciation of defense in baseball than at the present.
A wave of metrics over the past decade or so has changed the way people inside and outside the game view the value of fielding and measure the defensive prowess of individual players.
Defensive runs saved and zone rating have become two of the top advanced statistics to evaluate players. Defensive efficiency is generally considered a much better stat to determine how well a team fields than the traditional fielding percentage statistic.
All 30 major league teams also have proprietary defensive measures.