In examining the factors that contribute to the end of relationships, the factors supporting their sustainability are considered in parallel here. The structure of the network itself is modified by these losses, and conversely, the structure affects the strength of the ties. We combine both an overview of these movements and the finer patterns of ending and continuation of relationships.

How do networks behave with regard to spatial divisions, do they respect or transgress distances, qualifications of spaces, mobilities? Can the development of new means of communicating over distance change this relationship of networks to space? Where do our relatives or, more generally, those with whom we are in contact live? Are we close (spatially) to our close (emotionally) ones ? What are the effects of urban evolutions on relational structures? How does spatial mobility influence networks? This is the issue of the spatial dimension of personal networks or, to put it another way, the link between "spatial" proximity and "relational" proximity. We show the importance of the local (city-wide) dimension of networks, but also their ability to retain their structure after mobility, despite significant changes in their composition.

Different relational dynamics make relationships evolve within entourages. They are here mainly explored from the Caen panel, whose longitudinal dimension allows it to capture detailed movements over time. The diagram of relational dynamics identified in Chapter 3 is taken up again by detailing the main movements articulating relations, contexts and networks: polyvalence/specialization, singularization/embedding, and connection/dissociation. The ways in which these dynamics appear, their frequency, and their evolution over the time of the relationship, and over biographical time, are highlighted here.

The subject of this book is social relations, the concrete ties that are established between individuals, and the networks these ties constitute. Family members, friends, neighbors, business or work colleagues, romantic partners, vague acquaintances: all play a part in people’s lives, helping, influencing, and giving them ideas, but also preventing them from doing certain things. Some they entrust with little secrets and problems; with others they share leisure time and evenings out. When this network changes, life also changes to a greater or lesser extent. Conversely, a significant change in life has repercussions on the individual’s network: he sees less of certain friends and more of others who more closely match new concerns and desires. The aim of this book is to offer an overview of social relations and their dynamics at the level of individuals and their social surroundings. We draw, firstly, on two surveys we carried out and, secondly, on the accumulated findings of the tradition of social network analysis.

Social relations are defined by considering the different dimensions involved: interaction, knowledge, emotional involvement, and, more generally, the "driving force" of the tie, which are its essential elements. This characterization of relationships is continued by mentioning qualities that are very important for their becoming: the multiplexity and "strength" of the ties. To explain the link between relationships, networks, and social circles, the different scales at which the entourage can be considered are then evoked. The questions of the homogeneity of relationships, the resources they may constitute, as well as the different ways in which they can be inscribed in social circles are also addressed. Finally, the various types of regulation involved in the positioning of relationships are presented.

Here, we can further clarify what can be linked to the life stages in the changes occurring in personal networks. The periods of network reconfiguration that take place within the life cycles are analyzed on the basis of statistical data. The family of origin gives way partially to constructed relationships, which are largely renewed and then undergo the impact of the transition to retirement. A more detailed analysis of the particular period of entry into adult life is carried out, looking at some of its key moments through a few typical cases of "ordinary" transitions but also through the trials of less common events.

How did networks develop over time, how are relationships from different life periods articulated today, how does the structure of the network evolve? By observing, in particular, how links aggregate and how they dissociate from each other, how they merge into social circles, or, on the contrary, tend to break free from them, the authors identify some processes of network evolution. These dynamics show their sensitivity to the impact of certain events, particularly during transitions to adulthood.

The game of affinities, which, depending on the context, favors more or less the establishment of relationships with people sharing similar characteristics, is discussed here. We begin with the formation of couples and the well-studied phenomenon of "homogamy," and then broaden the focus to its equivalent for general social relationships, "homophily." Social inequalities leave their mark on the characteristics of networks, on their arrangements with social circles, and on the evolutions of the interpersonal relationships that compose them. Even the elective affinities that we would like to believe as "free" of these burdensome social categories are in part subject to them. This chapter describes what can be called "soft segregation," that is, the fact that freely chosen relationships can paradoxically contribute to the fragmentation of the social world.

Relationships are not only an expression of sociability and the pleasure of being together. They also have a "utility" dimension: under certain conditions, they are a means of accessing resources. People who are in a relationship provide each other with many services, but these services alone are not enough to qualify relationships. This chapter examines the way in which relationships and networks can become resources, particularly economic resources, but also form the basis of daily mutual aid and influence. The best known case is that of the labor market, but the "economic" use of relationships goes far beyond that. Mutual aid and social support, but also influence within the personal network are other forms of relational resources.

The authors begin by describing the theoretical framework on which they have based their analysis of the processes they present in this and subsequent chapters. It seeks to account for the interactions between circles, relationships, and networks and to keep in mind that one does not exist without the others. Three main types of contexts for the emergence of relationships are then successively explored: their construction within a social circle; interactions around shared issues; and the extension of the network by the introduction of people through shared relationships. Once constructed, relationships acquire a certain autonomy regarding their context of emergence, which can be captured by the way respondents designate them. Finally, this chapter ends with a review of how social differences (age, gender, level of education, occupation) are perceived (and partly elaborated) in the processes of relationship construction.

Various characteristics of the networks are examined: their composition, density, homogeneity and dispersion. Their overall structure can be very varied, and therefore builds contrasting environments. Using examples, various personal network profiles are described by analysing the social issues that lie beneath their differences. The study of personal networks, their distribution, their temporal strata, their diversity, and their degree of interconnection, therefore allows us to approach a kind of dynamic social mapping of the modes of circulation and anchoring in social worlds. To better grasp the particularities of personal network analysis, the authors briefly explore a few examples.

All of these analyses raise the question of the inclusion of networks in society: do networks reproduce inequalities, do they possibly reinforce them, or do they still offer small spaces for "play" among social constraints and divisions? Do they constitute for the social sciences an intermediate level of observation, or a relatively autonomous dimension of social life, bearing its own logic and its own dynamics? We have tried here to shed light on some of these dynamics, as part of the implementation of the principles of a relational sociology.

At the beginning of the 1990s, the Internet was starting to become fairly widely used in academic circles. This development raised questions within the community of social science researchers who were studying social networks. Among them was of course that of the changes in relational flows and structures (connectivity, size, density, and composition of personal networks, etc.) that might occur as a result of the increasing diversification and sophistication of communication technologies. For this chapter, we draw on two recent original surveys in addition to the two on which our analyses have so far been based. The first is a questionnaire-based survey conducted in January and February 2014 among 2,700 young people aged between 15 and 25 living in the Toulouse area. The second survey is a detailed questionnaire filled in during face-to-face interviews by some 470 individuals aged 60 and over (the oldest was 100 at the time of the survey) in the Toulouse area. The changes seem to be tending in the direction of a slight reduction in strong ties, an increase in weak or even very weak ties and a strengthening of relational inequalities and homophily.