This study examined forces leading Korean cities to join the WHO Global Network of Age-Friendly Cities and Communities (AFCC) and implement the WHO guidelines, from the perspectives of multiple streams theory and policy transfer theory. We conducted interviews with stakeholders from six member cities and identified relevant themes using directed content analysis. Political motivation was the strongest factor in seeking Network membership, but the lack of political motivations after gaining membership resulted in lackluster local implementation efforts. The national capital cities may need to take a stronger leadership role to encourage the expansion of the WHO AFCC Network in Asia.