We examine the systemic conditions that have influenced the electoral success of parties of the extreme right in West European politics from 1970 through 1990. Empirical estimates based on 103 elections in sixteen countries suggest that electoral and party-system factors interact with each other to generate conditions conducive to these parties. Specifically, increasing electoral thresholds dampen support for the extreme right as the number of parliamentary parties expands. At the same time, multi-partism increasingly fosters parties of the extreme right with rising electoral proportionality. Our analyses also indicate that higher rates of unemployment provide a favourable environment for these political movements. These results suggest that levels of electoral support for the extreme right are sensitive to factors that can be modified through policy instruments.