(2S)-trans-4-Hydroxyproline has been studied as a chiral template for the preparation of kainoids. Conversion to protected 4-ketoproline derivatives has allowed functionalisation at C-3 to be investigated. Although the tendency to epimerisation has caused problems, we have successfully introduced a variety of alkyl side chains with cis stereochemistry at this position. Functionalisation of the 3-alkyl-4-ketoprolines at C-4 has been investigated and a method has been found to prepare compounds which are functionalised stereospecifically at both C-3 and C-4. These have potential for study as kainate analogues. During our studies on the synthesis of kainoids, an unusually stereospecific deuteriation has been discovered. We have exploited this in a synthesis of (2S,3S)-[3- 2Ht]-proline, (2S,3R)-[3-2Ht]-proline and (2S)-[3,3-2H21-proline.