Committee parliamentary specialization index. Explaining mps’ specialisation in the Spanish Congreso de los Diputados Oñate, Pablo Ortega Villodres, Carmen Parliaments Commitee system Mp specialisation and expertise Nowadays legislatures are largely based on committee systems. This enables a division of work and specialisation, in the context of highly complex politics and policy development. It seems clear that MP specialisation in the field of the committee they serve on is an important political asset, both for MPs and their parliamentary party group. This paper presents the Committee Parliamentary Specialization Index. This index measures the degree an MP is specialised in the jurisdiction of the committee they serve on. In the second part of the paper, the index is applied to the Spanish Congreso de los Diputados, an interesting case for testing this multi-faceted index, to find institutional, political and individual factors that better explain the degree of MP specialisation. 2024-01-30T12:11:03Z 2024-01-30T12:11:03Z 2019 journal article JOURNAL OF LEGISLATIVE STUDIES https://hdl.handle.net/10481/87656 10.1080/13572334.2019.1662610 eng embargoed access