This chapter discusses methods of analysis of concrete and aggregate samples to determine their alkali content and potential availability to contribute to alkali-silica reaction (ASR). Sample size and representativity are important considerations for any test method, and these are discussed as a pre-requisite to sample acquisition and preparation. Preparation methodologies appropriate to aggregates and concrete are discussed, with detailed guidance offered for a range of analytical techniques. Guidance on conducting the analysis by wet chemical methods, X-ray fluorescence (XRF), atomic absorption spectroscopy (AAS), inductively coupled plasma spectroscopy (ICP), in-situ elemental analysis by scanning electron microscopy (SEM) or electron microprobe analysis (EMPA), and ion-selective electrodes is presented. Finally, guidance is provided on reporting analytical results and accounting for analytical error.