The impact of AS (alternative splicing) is well-recognized in animal systems as a key regulator of gene expression and proteome complexity. In plants, AS is of growing importance as more genes are found to undergo AS, but relatively little is known about the factors regulating AS or the consequences of AS on mRNA levels and protein function. We have established an accurate and reproducible RT (reverse transcription)–PCR system to analyse AS in multiple genes. Initial studies have identified new AS events confirming that current values for the frequency of AS in plants are likely to be underestimates.