Universidad de Oporto "words or expressions that may always have the same meaning when applied to one kind of thing, but have different meaningwhen applied to another kind of thing" (Flew, 1979: 11) RESUMEN Este trabajo tiene como principal propósito contribuir a la clarificación del concepto de competencia, a la luz de los desafíos que actualmente tienen la formación y el desarrollo de la competencia. Se comienza por reflexionar sobre las cuestiones léxicas, relacionadas con los significado(s) de competencia, luego nos centramos en el debate en torno al concepto(s) de competencia, preferentemente en áreas de formación, evaluación y desarrollo profesional. Tras el análisis efectuado emerge la idea de que no existe un solo constructo teórico de "competencia", sino que coexisten varios en campos conceptuales diferenciados ya que el concepto de competencia es un concepto complejo, holístico, integrador y de naturaleza relacional. La competencia se presenta como algo situacional; ocurre en la acción, no es directamente observable; se relaciona con el éxito, pero no se confunde con el desempeño concreto.ABSTRACT The main purpose of this study is to contribute to the clarification of the concept of competence in light of the new challenges the education and development of competence has to face nowadays. After a brief review of lexical issues related to the meaning(s) of competence, the analysis is focused on the debate concerning the concept of competence occurring within such areas as professional education, evaluation, and development. The analysis support the idea that rather than a unique construct of competence, there are several dissimilar conceptual fields, portraying competence as a complex, holistic, integrative, and relational concept. Competence is situational, it is reflected in action, it is not directly observed, it is related to the outcomes but it should never be confused with any particular performance.