ratified by Costa Rica on August 12, 1999. This Convention uses a social model in its approach to disability, meaning that disability is not defined exclusively by the presence of a physical, mental, intellectual, or sensory impairment, but is rather interrelated with the social barriers or limitations preventing persons from exercising their rights effectively.55 The types of limitations or barriers commonly encountered by functionally diverse persons in society are, among other things, physical or architectural barriers, as well as communication, attitudinal, or socioeconomic barriers.56 52. Additionally, the Court highlights that on May 3, 2008, the Convention on the Rights of Persons with Disabilities (hereinafter the “CRPD”) entered into force. This Convention establishes nondiscrimination as one of its general principles and prohibits all discrimination on the basis of disability.57 The CRPD, which was ratified by Costa Rica on October 1, 2008, establishes a series of guiding principles regarding the rights of persons with disabilities, including non-discrimination; full and effective participation and inclusion in society; and accessibility.58 It also recognizes states’ obligation to “refrain from engaging in any act or practice that is inconsistent with the present Convention and to ensure that public authorities and institutions act in conformity with the present Convention.”59 53. This Court also emphasizes that, in compliance its special protection duties regarding any person facing vulnerability, the state must adopt positive measures to protect rights, determined according to the particular needs for protection of the bearer of the right, whether due to the bearer’s personal condition or the specific situation facing the individual, such as disability.60 In this sense, states have an obligation to strive for the inclusion of persons with disabilities by offering equal conditions, opportunities, and participation at all levels of society61 in order to guarantee that legal or de facto limitations are dismantled. States must therefore promote social inclusion practices and establish affirmative action measures to remove these barriers.62 In this regard, as indicated by expert witness Sylvia Quan, attitudinal barriers are a particularly significant obstacle to the exercise of rights by persons with disabilities "due to prejudices, stigmas, and discrimination in multiple forms."63 54. Based on the same logic, the Court notes that persons with disabilities are often subject to discrimination based on their status, and therefore states must take every legislative, social, educational, workplace, or other measure necessary to ensure that Cf. Case of Furlán and Relatives v. Argentina, supra, para. 133, and Case of Vera Rojas et al. v. Chile, supra, para. 102. 55 Cf. Case of Furlán and Relatives v. Argentina, supra, para. 133, and Case of Vera Rojas et al. v. Chile, supra, para. 102. 56 57 Cf. CRPD, articles 3 and 5. 58 Cf. CRPD, article 3. 59 CRPD, article 4. Cf. Case of Ximenes Lopes v. Brazil. Judgment of July 4, 2006. Series C No. 149, para. 103, and Case of Manuela et al. v. El Salvador, supra, para. 257. 60 Cf. Case of Furlán and Relatives v. Argentina, supra, para. 134, and Case of Guachalá Chimbo et al. v. Ecuador, supra, para. 86. 61 Cf. Case of Furlán and Relatives v. Argentina, supra, para. 134, and Case of Guachalá Chimbo et al. v. Ecuador, supra, para. 86. 62 63 Expert opinion of Silvia Judith Quan Chang (evidence file, audiovisual material folder, min. 2:10). 17