Summary.Measures of formal and informal authority structure were employed in order to assess academic and non‐academic outcomes of individualised instruction. A sample of 386 fourth and fifth‐grade elementary school children studying in nine individualised and 10 traditional classes was employed. This academic outcomes of either method of instruction were found to be contingent on the congruence between formal and informal authority structure: higher achievement scores were obtained when individualistion as school policy was accompanied by teacher sharing of authority with pupils at the informal classroom level. Achievement in less individualised classes was higher when teacher did not extend decision‐making opportunities to pupils. Non‐academic pupil outcomes were generally unrelated to either formal or informal authority structure. Similarities and differences between these results and former findings are discussed in light of cross‐cultural differences in classroom individu