There is evidence deriving from the consultations carried out at the University of Alcala Legal Clinic that people living with HIV (PLHIV) face several barriers in purchasing private health insurance. Given that the Spanish National Health System does not provide for universal access to healthcare, a refusal of private health insurance could result in a denial of access to healthcare. PLHIV in most cases encounter these barriers due to the stigma and prejudice surrounding their health condition. In that regard and in light of the conceptualization of disability offered by the UN Convention on the Rights of Persons with Disabilities (CRPD), PLHIV may be regarded as persons with disabilities and fall within the scope ratione personae of the CRPD. Article 1(2) CRPD states that “persons with disabilities include those who have long-term physical, mental, intellectual or sensory impairments which in interaction with various barriers may hinder their full and effective participation in society on an equal basis with others”. Against this background, this PhD thesis aims to answer the following overarching research question: Do PLVIH have a human right to access to private health insurance in Spain? In answering that question, this thesis embraces a human rights approach to disability in line with the CRPD. It is grounded on traditional legal desk-based research and falls within the remit of a multilevel constitutional analysis. In particular, while focusing on the Spanish legal system, it adopts a multilevel perspective: it looks at Spanish law in conjunction with relevant international law (with particular reference to the CRPD) and European Union (EU) law and discusses how those interact with Spanish law. After having introduced the issue underpinning the research question, the thesis addresses the relevant human rights and how they are protected in a multilevel context: right to equality and non-discrimination, the right to health, and the freedom to conduct a business. It then examines how these rights interact with each other. First, the thesis discusses the protection against discrimination afforded in a multilevel system, with particular reference to the concept of inclusive equality provided in the CRPD. On the basis of this analysis, it assesses, through the lens of equality, the fourth and fifth additional provisions of Law 50/1980 on insurance contracts. Those provisions prohibit the denial to access private insurance on the ground of disability unless this action is based on justified, proportionate and reasonable causes, previously and objectively documented. The thesis argues that, despite their proclaimed purpose, these provisions fail to protect PLHIV (and, more generally, persons with disabilities) from discrimination. In fact, those provisions only require the application of general standards of review in cases of non-discrimination between private parties on one of the grounds protected under Article 14 of the Spanish Constitution of 1978 (including disability). Namely, a company under certain circumstances can be compelled to contract with another private party unless its refusal to contract stands a proportionality test. Those circumstances are: the company holds a dominant market position; the company offers services to the public that affect important human rights (health, dignity, physical and moral integrity, etc.). This type of framework is only useful for exceptions, and it usually requires a Court decision. Therefore, the above-mentioned provisions by ignoring the structural discrimination on this context allow de jure and de facto for differential (and detrimental) treatment on the ground of disability. Secondly, the thesis explores Article 43 of the Spanish Constitution of 1978 and highlights, on the basis of well-established scholarship, the rights that this Article grants: the possibility for the individual to decide on matters related to its health; protection against actions and decisions aimed at preventing people from deciding over their own health and the possibility of demanding that the State performs its duty in such a manner, so the health of no individual is violated by other private party. Furthermore, on the basis of an historical and teleological analysis of the provision, as suggested by the most renowned constitutional scholarship, the thesis contends that the right to health includes a right to non-discriminatory access to healthcare. This interpretation is also supported by a reading of this constitutional provision in light of relevant human rights law, namely the International Covenant on Economic, Social and Cultural Rights, the CRPD, and the European Social Charter. Therefore, it is suggested that the current application of the fourth and fifth additional provisions of Law 50/1980 on insurance contracts is also in breach of both constitutional and international provisions on the right to health as it does prevent access to healthcare. Finally, the thesis examines whether and to what extent limitations of the right to health and derogations from the principle of non-discrimination could be justified in order to protect the freedom to conduct a business. Given that the denial of private health insurance could have an irreversible impact on the dignity, the right to health and the right to physical and psychological integrity, and ultimately the right to life of PLHIV, and more broadly persons with disabilities, this thesis argues that the protection of the freedom to conduct a business cannot justify a denial of access to healthcare. Concluding otherwise would have led to affirm that the protection of the freedom to conduct a business takes precedence over the right to life. On the whole, this thesis argues that placing upon insurance companies an obligation to adhere to an open enrollment system and a risk compensation scheme would in fact be compatible with the freedom to conduct a business referred to in Article 38 of the Spanish Constitution of 1978 and would also comply with EU law. In particular, this PhD thesis suggests that the above-mentioned measure would be not only in compliance with the Spanish constitutional framework and desirable from a practical point of view, but would also avoid for Spain to be in breach international obligations. Since private health insurance continues to be of key importance to exercising the right to health on equal terms with others, the legal reform put forward by the thesis will be the most suitable mean to ensure equal access to healthcare to PLHIV.