SUMMARYSamples from 70 horizons from UK soils were tested for structural stability, and a comparison was made between the results from the following six tests: (i) Emerson, (ii) Janse&Koenigs, (iii) Thorburn, (iv) Childs (soil moisture characteristic), (v) Williams&Cooke slump test, and (vi) wet sieving. Both correlations and systematic differences were observed between the tests, suggesting that different aspects of stability were emphasized by different test procedures. The tests leading to classes (i), (ii) and (iii) were found to be more subjective than those leading to indices. It is suggested that (v) may be applicable to less stable soils, and (vi) to more stable soils. Childs’ test was time consuming and subject to some erratic results; two new indices of stability are proposed to increase the reliability of this tes