In two laboratory experiments (N¹ = 84, N² = 20) the impact of goal setting on information processing (perception) in letter-matching tasks was examined. It was expected that setting difficult goals for reaction times improves performance because identification and especially semantic classification of letters should be speeded up under goal-setting instructions. Three findings can be emphazised. (1) Current models of simultaneous letter matching are incomplete because they do not account for differences in reaction time based on alphabetic variations (lower case vs. upper case letters) within a pair of letters that are largely independent of real letter sizes. (2) In both experiments and for all types of letter pairs (AA, Aa, Ab AB), goal-setting effects are found as expected. In addition, the explanation that these effects are due to a speed-accuracy trade-off can be excluded. (3) Moreover, in some conditions goal-setting effects are also influenced by special features of letter pairs. Specifically, goal-setting effects are especially strong for letter pairs in which the right letter was enlarged and in which alphabetic differences and semantic differences within pairs call for opposite answers (Aa, AB). Based on the overall pattern of results, it is concluded that difficult goals lead to a general facilitation of processes in visual perception and, in addition, to a reduction of stimulusinduced, performance-delaying inhibition processes if linguistic information is processed predominantly in the left hemisphere.