Scandinavian countries dominate happiness rankings through welfare state architecture & economic equality. Finland achieves consecutive 1 rankings 2018-2024. Denmark ranks 1 in 2012, 2013, 2016. GDP per capita of $45,000-$75,000 enables prosperity. Gini coefficient of 0.25-0.28 enables equality. Interpersonal trust of 60-70% enables social capital. Yet high suicide rates & seasonal affective disorder reveal hidden challenges. Replication requires selective policy adoption & long-term commitment.