A universal basic income (UBI) is defined as a universal, unconditional cash payment that is made regularly, is sufficient to live on, is not means tested, carries no work requirements and is paid on an individual basis. This study examines the international evidence on universal basic incomes and identifies key issues for consideration in the design of any UBI pilot for Ireland. Despite the mainstream interest in UBI as a potential policy tool, relatively little is known about the associated consequences of such policies. Even the definition of a UBI appears to be poorly understood and is often misused in the public discourse. Several pilot studies have been recently implemented across different countries. However, some pilot studies depart from the accepted definition of UBI. For example, some are not universal, in that they only target a specific subgroup of the population and/or have eligibility restrictions based on earnings. Others provide a relatively low level of payment, which may fall short of what an individual could reasonably be expected to live on. There are a number of potentially positive impacts associated with a UBI. A universal, unconditional payment could eliminate the stigma associated with welfare receipt. If replacing existing welfare payments, a UBI would also involve lower transaction costs, both on the recipient (in terms of the application procedure) and on Government (in terms of administering the payment). Universal, unconditional payments would also avoid situations where people choose not to work in order to retain means-tested benefits. UBI could give individuals the freedom to turn down or leave insecure, exploitative or low-paid work in pursuit of better or improved work opportunities. In addition, it would mean that persons in informal and often unpaid work, such as childcare and eldercare, which is mostly done by women, receive some compensation for their labour. Empirical results from several pilot studies have found evidence of positive health impacts following the implementation of a UBI. In terms of potential disadvantages, a UBI, by definition, may not target those that are most in need, as a large percentage of recipients will be high-earning individuals. Furthermore, the cost of a UBI is likely to be very expensive, even if other existing benefits (such as unemployment benefits) are no longer required. The net impacts of a UBI on labour supply are unclear, with both positive and negative influences on labour market participation potentially arising as a consequence of a UBI. In this study, we undertake some basic calculations relating to four possible UBI approaches, all of which would involve an unconditional payment to every individual aged over 18 in Ireland.