In low-resource settings, like Uganda in Africa, fever is commonly measured by means of tactile contact with skin. However, for patients, caregivers and healthcare workers, self-assessment of fever is significantly inaccurate. Inadequate healthcare leads patients to be over-diagnosed with malaria and therefore over-treated with antimalarial medicines. Moreover, misdiagnosis results in neglected treatment for patients with non-malaria febrile illnesses, which in turn brings related risks for the patient. This project aimed to investigate the current barriers for accessible and reliable fever diagnostics and to develop a new ‘frugal fever diagnostics’ product service system (PSS) including a fever diagnostics device and connected health services, with the focus on the interaction between the users and the device as well as the interaction between the device and the eco-system. One of the challenges in this project was to develop a product service system for the healthcare system, which is a large social system, involving many participants and roles in addressing the recovery of individual. Therefore, the research employed a Context Variation by Design approach to explore the topic of the research with a holistic perspective and to gain diverse insights from different parts of reality. Firstly, five types of factors that impeded people to have adequate fever assessment in the Ugandan health system were identified from the literature review. Based on the findings, three considerations were proposed that could give an impact on how fever diagnostics are designed and implemented in low-resource healthcare systems. Firstly, the fever diagnostics journey shows the involvement of people in the different phases of diagnostics, from awareness to monitoring and a follow-up. Secondly, there are different user groups of thermometers within the same healthcare system and those user groups have different conditions of access to fever diagnostics. Lastly, these different users have different needs regarding the information that was offered. The healthcare system in Uganda is separated into public and private providers, and it is clear that the choices available for communities in low-resource settings were limited. In order to enhance the access to fever diagnostics in these contexts, specific and potential user groups and their needs should be looked at. Based on the insights, the informal healthcare sector was selected as the promising innovation opportunity for the development of a new ‘frugal fever diagnostics’ PSS. Since the people in Uganda have the common perception that care for febrile symptoms is sought from the informal sector before visiting the formal sector, an informal provider is the first touchpoint in the fever diagnostic journey. However, the informal provider was the only provider that does not make a diagnosis before selling medicines among the health providers visited by the febrile people. Therefore, those people, who have no access to the formal healthcare, need to be provided access to fever diagnostics in the remote communities. Besides the study on the barriers of access to fever diagnostics in Uganda, six different types of thermometers were evaluated in order to identify optimal features of a frugal thermometer. It was revealed that measuring temperature with an infrared sensor on the forehead is suitable for the informal healthcare context. In addition, a large display with a numerical and colour-coded reading could make the use-flow simple and easy. Those findings were applied to design frugal thermometer concepts in a later phase of the project. Healthy Entrepreneurs (HE) was involved as a good example of the informal health sector. HE is an organization offering access to health information, and reliable, affordable essential medications and health products for households in resource-constrained countries. Through the research on the fever diagnostic provided by HE, the fever diagnostic journey of the people in the remote community was understood and beneficial innovation opportunities were selected among several insights in order to develop a preliminary ‘frugal fever diagnostics’ PSS scenario. The scenario included three perspectives: helping the patients to obtain the information they need for their febrile symptoms, combining a temperature measuring service with the Rapid Diagnostic Tools (RDTs), and cooperating with the formal health sectors to improve the quality of care for patients with febrile illnesses. These perspectives were translated into two solutions in the preliminary PSS. Firstly, a fever case management service was adopted to enhance the rational use of medicine and good quality of treatment for febrile diseases by implementing temperature taking services and RDTs. Secondly, temperature data collection was included to build the frugal fever diagnostic service system. Through an evaluation workshop of the preliminary scenario with the stakeholders, two ideal fever diagnostic PSS scenarios were identified based on the preliminary scenario. One of the scenarios focused on utilizing temperature data in the fever management service provided by Healthy Entrepreneurs to identify appropriate care for febrile patients. Another scenario focused on collecting temperature date for scientific and epidemiological research purposes in order to study febrile diseases and their treatment. Based on the insights from the evaluation, two fever diagnostic PSS concepts were designed. The PSS concept for HE incorporated the fever management in the service system of HE in order to provide inexpensive and reliable fever diagnostics, and the access to complete and relevant diagnostic information in the remote communities. Another PSS concept integrated temperature data collection through the fever management service for a broad range of scientific studies. Both PSS concepts were supported by physical evidence: the tablet, the frugal thermometer, the Rapid Diagnostic Tools (RDT) and the referral. A free fever temperature taking service, a rental thermometer service and a RDT are provided as a fever management service, in order to attain an investigation of non-febrile people and non-malaria febrile people, and deliver the relevant care for their symptoms. Within the PSS design, frugal thermometer design concepts were proposed to facilitate the process of fever diagnostics by the Entrepreneurs and by the care seeker, and the temperature data collection. Ultimately, two final PSS designs and a final frugal thermometer design were proposed after the evaluation with the stakeholder. For further development of the project, the considerations regarding to the final PSS designs and the frugal thermometer were discussed.