<p>Since the 1960's, the Police has become an historiographical subject. This field was, in the beginning, an offshoot of the study of crime. Yet since the 1980's the developments in police history, first in the Anglo-Saxon and lately in the French world, proved that it can be an autonomous field in dialogue with criminal justice, urban, political and labour history. If the nineteenth century and early twentieth were the main focus, recent developments have witnessed a growing interest in the latter decades of the twentieth century. The development of the field has driven to new approaches and sub-specializations. These can be summarized in three different areas.</p><p>One line research, more connected with political science, studies the different institutional systems under which different kinds of police institutions emerged and developed. In this approach, the distinction between urban and rural police, the dichotomy military vs. civil model, the central-local state tensions, or the political costs of police actions are major themes (Bayley,1975; Liang,1992; Emsley,1999; Blaney,2007; Cerezales,2008).</p><p>Another kind of approach has been focused on the study of the internal dynamics of police organizations and police work (Shpayer-Makov,2002; Emsley,2000). In the nineteenth century, urban police and policing was marked by the progressive emergence of modern formal organizations, constituted by paid, civil men acting full-time. Then, from early twentieth century, the appearance of specific police techniques and ideals of efficiency settled the emergence of professionalism. The constitution of police organizations and the transformations of police professionalism are then the main themes of this line. The first thesis of this research line tended to emphasize the views of police chiefs and politicians. More recent, with the use of different sources (for example, oral history for more recent periods), some works have showed the views of street-level policemen, attesting the complexities and ambiguities of policing in daily routines practices. Also in this type of approach, the police is seen as a specific socio-professional group, producing its own culture and ways of living (Brogden,1991; Weinberger,1995; Merriman,2006; Berli&egrave;re et.al,2008). These approaches have showed how police can be a frame that, acting upon the citizens, had significant social effects on the ones that performed policing.</p><p>Finally, a third type of approach concentrates on the relations established between police(men) and local communities (Thale, 2007).</p><p>This kind of approach has led to an examination of the development of the forms of police organization in straight connection with, and as a result of, the interactions with the population. If until the 1920's, it is possible to identify the predominance of a territorial organization, in which the physical proximity between policemen and the population (Ogborn,1993), from the 1930's onwards the introduction of new technological devices changed the way in which police was settled in the urban space (Reiss,1992; Holdaway,1980). These are the authors that more carefully have examined the multiplicity of tasks performed by the police, discussing the construction of police mandate as a dynamic process, resulting from the interrelationships between the political, the organizational and police-public interactions (Lipsky,1980; Monjardet,1996).</p><p>In Portugal, the works dedicated to police history were until recently sparse and only indirectly focusing on the police, with crime and political surveillance constituting the main subjects. Recent years had, however, witnessed an upsurge of works addressing directly the police, showing that this can be a fruitful field to apprehend the dynamics of Portuguese contemporary history.</p><p>A number of works have been focused in the second half of the eighteenth century with the emergence of the police state. As part of state history (Subtil,1989a) or in the field of urban history (Lousada, 2005), the Ancient Regime meaning of police had already been subject of a considerable amount of attention.</p><p>The emergence of the liberal state after 1834 was marked by increasing efforts to reform and modernize police institutions. The creation of Pol&iacute;cia Civil, in Lisbon, Oporto and other district capitals, constituted a cornerstone in this transformation (Santos, 2006).</p><p>At this point we can rightly identify the birth a modern model urban of police (professional and paid). This meant the setback of traditional ways of policing: non-paid agents (Pata, 2001; Catroga,2006; Santos,2001) or the military (Cerezales, 2008). Pol&iacute;cia Civil has concentrated the efforts of some social historians trying to understand how organization worked and the practices and life of the men that constituted police organization (Vaz,2007; Gon&ccedil;alves,2008; Garnel,2007).</p><p>As we advance to the twentieth century the number of existing works reduces drastically. Political policing has been a fruitful field (Ribeiro,1995;Pimentel, 2007), with valuable clues to the study of urban policing. But it is in the field of Anthropology that we can find the most significant contributions to understand urban police in Portugal. Some of the principal mutations occurred inside PSP in the last forty years, for example,the first policewomen (Leandro,2006), the social and cultural construction of police work (Dur&atilde;o,2008 [2006]), or the way police produces marginality (Bastos,1997) have all been worked by anthropologists.</p><p>Considering the international trends, is in the relation between the second, focused on the organization, and the third, which examines police public relations, that this project will stand. Our hypothesis is that we can only fully understand political options if we relate them with the material and operational context in which the police acted, and in which multiple relationships with urban communities happened. </p>