Radiogenic strontium (Sr) isotopic compositions (87Sr/86Sr) of different earth and extraterrestrial materials have been measured since the 1950s to understand various earth and planetary systems and constrain their timings. The Sr isotopes have been widely used in geochronometry (Rb–Sr dating), constrain ages of marine carbonates (87Sr/86Sr stratigraphy), assess past and present continental weathering, and understand sedimentary provenance. In most of the natural/geological materials, Sr is incorporated as a trace element, necessitating careful extraction, preconcentration, and purification prior to isotopic analysis using a mass spectrometer. Further, careful analysis is required in a low blank environment for reliable Sr isotopic measurements. This chapter outlines key methodological challenges involved with the extraction and purification of Sr from various natural/geological samples with differing matrix compositions prior to mass spectrometric analysis.