Resumen: This work adds to the debate on corporate governance regulations and its effects on performance and firm value. The paper empirically tests whether there is a significant price reaction to corporate governance announcements following the publication of the Aldama Code of Best practice (2003) in Spain. In particular, news announcements are classified according to the code principles to distinguish among different dimensions of corporate governance and have a better understanding of investors'' reaction. Results show first, that investors react to this kind of practices, second, that the sign of their reaction depends crucially on the nature and extension of the recommendation and finally that firms that disclose more do not enjoy higher market prices or return on the medium-long term. Idioma: Inglés DOI: 10.1016/j.brq.2015.04.002 Año: 2016 Publicado en: BRQ Business Research Quarterly 19, 1 (2016), 13-25 ISSN: 2340-9436 Factor impacto JCR: 1.325 (2016) Categ. JCR: BUSINESS rank: 85 / 121 = 0.702 (2016) - Q3 - T3 Factor impacto SCIMAGO: 0.387 - Business, Management and Accounting (miscellaneous) (Q2) - Economics and Econometrics (Q3)