The current article examined educational achievement at lower-secondary level in Sweden (Grade 9), using grades and national test results (NTR) as the dependent variables. Linear regressions and bivariate correlations indicated that the proportion of highly-educated individuals in each municipality was positively associated with grades and NTR and that the proportion of welfare recipients and non-natives, as well as rural location, had negative associations. In relation to two case studies with fewer observations, teacher certification rates were more strongly correlated with higher achievement measures. Overall, the NTR of Swedish as a second language (SVA) pupils lowered the overall results in most municipalities. For instance, in low-performing municipalities the native students' NTR was virtually identical to that of the "high-performing" or "best" municipalities when SVA scores were removed. Thus, it seems misguided to highlight "successful" school municipalities whose performance is only average.