Between the years 2004 and 20007, road accidents and victims in Spanish roads have experimented an important reduction, resulting from the adoption of a set of legislative and control measures. During the same period, the numbers of accidents and victims for van-involved accidents increased, departing from this general trend. Research on the influence factors for the behavior of this type of vehicles was carried out under the frame of a project funded by the Spanish National Research Plan, leaded by INSIA and with participation of the research groups of TRANSIT (a transport research center in Universidad Politecnica de Madrid), ISVA (Institute of Vehicle Safety) of Universidad Carlos III, and IEA (Automotive Institute) of the Spanish Association of Car and Truck producers, (ANFAC). The main research activities and methodologies applied have been: definition and characteristics of the Spanish van fleet vehicles and classification into four conceptually different van types from both the construction and use viewpoints. Data analysis for a sample of in-depth revised accidents; track tests for vehicles representing some of the van-types as identified above and comparison with passenger cars; nationwide survey on more than 3600 drivers; urban mobility study with instrumented vehicles, road inspections on a sample of vehicles. Study of the results of technical inspections of a large sample of vehicles; study of interurban van mobility; application of different statistical methods: data mining, DRAG and UC models for time series of accident number and severity. The activities developed constitute the “Integrated Methodology for Road Accident Research” (MIICA), a contribution of the Automobile Research institute (INSIA) which integrates statistical methodology and tools, tests and experimentation, simulation and computation. MIICA is integrated by means of a set of hypothesis, whose formulation is based on the experience of the research groups involved and the results published in other studies related to the accidental behavior and safety conditions of this type of vehicles. The 15 hypothesis formulated where concerned with vehicles (5), mobility and use conditions (6), and drivers (4). MIICA is a layer model under which different potential influence factors for the accidental behavior of groups of users and vehicles and their levels of influence and interrelationships are identified. The application carried out for the population of vans allowed for the development of results of their use and exploit, fleet characteristics, drivers and companies, which have been presented in terms of recommendations for the policy-enforcing institutions of the Spanish administration in charge of regulation and control of activity of this type of vehicles. Given the extension of the work developed, in this paper a brief description of the general planning of MIICA and its most relevant results is presented.