Abstract We calculate the O( α s ) corrections to longitudinal spin-spin correlations in e +e −→q q ̄ . For top quark pair production the O( α s ) corrections to the longitudinal spin-spin asymmetry amount to less than 1% in the q 2-range from above t t ̄ -threshold up to q 2 =1000 GeV . In the e +e −→b b ̄ case the O( α s ) corrections reduce the asymmetry value from its m=0 value of −1 to approximately −0.96 for q 2-values around the Z-peak. This reduction can be traced to finite anomalous contributions from residual mass effects which survive the m→0 limit. We discuss the role of the anomalous contributions and the pattern of how they contribute to spin-flip and no-flip terms.