A surfactant composition comprising: alkylarylsulfonate surfactant system comprising at least two isomers of the alkylarylsulfonate surfactant of the formula: ##STR1## wherein: L is an acyclic aliphatic hydrocarbyl of from 6 to 18 carbon atoms in total; M is a cation or cation mixture and q is the valence thereof; a and b are numbers selected such that said alkylarylsulfonate surfactant is electroneutral; R', R" and R'" are independently selected from H and C.sub.1 to C.sub.3 alkyl; both of R' and R" are nonterminally attached to L and at least one of R' and R" is C.sub.1 to C.sub.3 alkyl; and A is aryl; wherein: said alkylarylsulfonate surfactant system comprises two or more isomers with respect to positions of attachment of R', R" and A to L; in at least about 40% of said composition, A is attached to L in the position which is selected from positions alpha- and beta- to either of the two terminal carbon atoms of L; and wherein further said alkylarylsulfonate surfactant system has at least one of the following properties: said alkylarylsulfonate surfactant system has a ratio of nonquaternary to quaternary carbon atoms in L of at least about 5:1 by weight, when said quaternary carbon atoms are present; or percentage biodegradation, as measured by the modified SCAS test, that exceeds tetrapropylene benzene sulfonate.