Driven by the needs and requirements of mathematical research as well as scientific disciplines using mathematics, the NFDI-consortium MaRDI (Mathematical Research Data Initiative) will develop and establish standards and services for mathematical research data. Mathematical research data ranges from databases of special functions and mathematical objects, aspects of scientific computing such as models and algorithms to statistical analysis of data with uncertainties. It is also widely used in other scientific disciplines due to the cross-disciplinary nature of mathematical methods. The handling of research data in mathematics raises questions on the reproducibility of results, reusability and access to data. However, existing solutions are often specific to the question at hand, resulting in the general lack of a comprehensive data culture and corresponding infrastructure for mathematical research data that support the research process and implement the FAIR principles. Starting with the areas of computer algebra, scientific computing, statistics and machine learning, MaRDI will develop standards for confirmable workflows and certifiable mathematical results and provide new services that assist the research cycle up to peer-review in the publication process. Furthermore, by building the MaRDI portal as a decentralised and federated infrastructure the storage and accessing of data and knowledge will be facilitated in a manner that would perpetuate FAIR and open science principles.