In the early stages of testing new varieties, it is common that there are only small quantities of seed of many new varieties. In the UK (and some other countries with centuries of agriculture on the same land) variation within a field can be well represented by a division into blocks. Even when that is not the case, subsequent phases (such as testing for milling quality, or evaluation in a laboratory) have natural blocks, such as days or runs of a machine. I will discuss how to arrange the varieties in a block design when the average replication is less than two.