The entire world needs and seeks information to survive and thrive in the 21st century as a result of information acquisition, with doctors, lawyers, teachers, students and even the elderly all desiring information for their everyday activities. Researchers of different disciplines working at the various federal institutes in Nigeria are no exceptions to the craving for requisite information that will enable them successfully carry out their numerous research projects undertaken towards achieving sustainable national development. The aim of the study was to investigate the information needs and information-seeking behaviour of researchers at the Federal Institute of Industrial Research Oshodi, Nigeria. This study applied both quantitative and qualitative research approaches for the purpose of triangulation. The quantitative approach had a strong dominance over the qualitative approach in this study. This study adopted the positivist paradigm. The questionnaire, interview and observation data collection tools were the chosen tools used to collect data from researchers from the six departments of the Federal Institute of Industrial Research Oshodi and five professional librarians of the institute’s library. Out of 165 questionnaires that were administered to researchers, a total of 121 were returned (resulting in a response rate of 73%). Inaccuracies were identified in seven copies of the questionnaires which were discarded and not analysed. Therefore, usable returns totalled 114 (67%). Wilson’s 1999 model of information behaviour was used as the theoretical framework. This study revealed that both formal and informal sources were consulted by the researchers. It was important to note that the internet was the information source most commonly used by the researchers to obtain information. The institute’s library was poorly used because it contained outdated library materials and was not equipped with an internet facility. The researchers opted for the use of mobile phone/iPad, personally owned or sourced internet access and business centres (supplying internet services outside the institute) to access information sources for information. The study ascertained that there was undoubtedly an instituted library officially established within the institute to provide information to researchers. But due to socio-economic and political problems faced by the country Nigeria, predominantly with respect to the outlook of poor funding of sustainable library development concerns and the government’s lack of interest in research, outdated library collections and poor information provision services have become the given at the institute’s library. This ultimately brought about pessimistic reactions from the researchers. Among its recommendations, the study suggested that funding the institute’s library in order to update and replace outdated library collections is a priority. An information audit should be carried out to ascertain the current state of ICTs within the institute and the institute’s library should be equipped with an internet facility promptly. Adopting these recommendations would enable researchers to have limitless access to items of information they need for research as they seek for information. / Information Science / D. Phil. (Information Science)