Continuous Quality is an proven, effective approach of using automated tools to improve code quality, as part of a Continuous Integration process.
For every proposed change to the code, a wide range of metrics are run against the code. If the team's agreed thresholds aren't met, the change will be rejected by the Continuous Integration server. This helps to make quality an implicit part of a team's normal development process, and encourages continual refactoring.
Continuous Quality can be as simple as preventing whitespace being accidentally committed, or as advanced as using static analysis to limit the cyclomatic complexity of code.