The role of biraderi kinship networks has recently gained attention in U.K. elections. Biraderis are patriarchal and hierarchical kinship networks that are led by male elders and originate from Pakistan and Bangladesh. These networks have been accused of influencing selections and elections through bloc votes. Existing research into the actions and implications of biraderi in U.K. politics has examined these networks in isolation. To further understand and contextualise the actions and implications of biraderi networks in U.K. politics, I compare them to trade union networks. Trade unions are paid membership networks in which groups of employees take collective action to maintain and improve employment conditions. Using my two case studies, I focus on the Labour Party and ask two questions. Firstly, what are the implications of network influence for electoral choice? Secondly, are the actions of biraderi networks, and the implications of these actions, different to other networks? And if so, why? I use a combination of qualitative and quantitative data in the process of this inquiry. In chapter three, I use the analysis of 37 interviews with political and community activists to introduce biraderi networks and present their role in the selection and election of political representatives. In chapter four I use the same data to contextualise the role of biraderi and examine the relationship between biraderi networks and the Labour Party. In chapter five, I introduce trade union networks and use the analysis of 16 interviews with MPs, political activists and trade unionists to outline three aspects of the role that trade unions take in the selection and election processes: the legitimate aspect, the controversial aspect and the idealised aspect. In chapter six, the final empirical chapter, I ask which candidates receive support from trade unions. I build upon an existing dataset to analyse financial and in-kind trade union donations to the Labour Party. I find that biraderi and trade union networks both, to some extent, carry out five actions in the selection and election of political representatives: providing political education; providing financial and in-kind support; providing campaigners in selections and elections; selecting candidates; supporting the under-represented. I find that the implications of these five actions for voter choice are two-fold. On the one hand, networks can increase voter choice by providing political education and support to candidates who might not otherwise be able to stand for election. On the other hand, I find that networks can reduce electoral choice. Through a combination of legal and illegal actions, when elders control votes biraderi networks can at best restrict electoral choice and at worst remove it entirely. Although these networks carry out the same five actions, I do find that they differ in the way that they carry out some of these actions. I ague that there are three reasons for this: differing network structures; differing network motivations; and access to different resources to influence selections and elections. I argue that networks are motivated to influence selections and elections by instrumental desires to increase their political influence and power as well as ideological motivations to support the party. I find that political parties need networks to help to campaign and deliver political education. Networks can work alongside parties to do this but they can also takeover as political parties abdicate their responsibilities, effectively becoming the party on the ground in a constituency.