Abstract: | Numerous new parties have emerged since voters became less loyal to established political parties. A number of these survived and have been analysed intensely, especially green and radical right parties; many other new parties disappeared and have been neglected by party research. This article analyses the fate of all 30 political parties that entered parliament in the Netherlands or Belgium between 1950 and 2003. Qualitative comparative analysis is used to identify characteristics of both surviving and disappeared new parties. Conditions related to party origin (roots in civil society, organisational newness, initial programmatic profile) are scrutinised, as are conditions pertaining to the party’s developmental process (party organisational strength and the occurrence of defections or party splits). Surviving parties are characterised by strong, rooted organisations that have not suffered defections. Most disappeared parties lacked a strong organisation and roots and have experienced shocks that they could not absorb. Organisational newness makes new parties vulnerable. |