Although methods for discovering consensus sequences playa vital role in molecular biology, researchers often seem inattentive to the features and limitations of such methods, and so there are risks that criteria for discovering consensus sequences will be misused or misunderstood. To appreciate better the issues involved, methods for discovering consensus sequences are surveyed. Included are methods based on frequency thresholds, voting strategies, heuristics, neighbourhoods, and measures of inhomogeneity or information content.