This chapter considers how to transcribe and analyse words that you have recorded to work out the sound system of a language. We review the notion of a phoneme, broad and narrow transcriptions, minimal pairs and allophonic variation. We suggest ways to organise and manage your data to help you find patterns and identify any gaps in your analysis; and plan elicitation sessions. We discuss native speaker intuitions on phonology, and how to approach the identification of tone, phonotactics and prosody. We also cover experimental design and introduce some instrumental recording techniques and equipment for phonetic analysis. We discuss the issues to keep in mind when developing an orthography, including both linguistic and socio-political factors.