The spatial planning system and the changing roles of actors of the City of Zagreb in the period of transition are analyzed in the thesis. Main goals of the thesis are: to point at the advantages and disadvantages of the local community participation, notice main characteristics of spatial planning in Zagreb, determine connections in the network of relevant spatial actors and to point to the possibillities of the actor affirmation and integration to improve the spatial planning system in Zagreb.The interdependence of political, economic and social aspects of transformation after Croatia's achievement of independence and the followinginfluence on spatial planning are also analyzed. It is considered that as a result of redefined connections among actors, i.e. inadequate participation of the local community and the growing importance of the private sector, spatial planning is insufficiently affirmed in the postsocialist development stage. Case study of local communities and local commmittes of Novi Zagreb is reasearched which represent two features of local self-government before and after the achievement of Croatia's independence, with different levels of interest. Their institutional frame, function and the position in the actor-network are analyzed, using the stakeholder analysis tool. For the actor-interdependence analysis interviews and matrix of interest and influence are used. The main conclusions of the thesis are: Urban development in the transition period initiated the marginalization of the local community in spatial planning, with the introduction of new actors. The spatial planning system of the City Zagreb is defined by unequale power distribution in which the investors and city offices are the most influential. Local communities had a greater role in local planning, as opposed to the present local commmittes, with a predominantly advisory role. The marginalization of the local actors directed the civil sector to act in the field of spatial planning and progressively initiated the recognition of the civil sector as a relevant actor.