Sustainability assurance (hereafter ‘SA’) has been a significant area of development in corporate reporting during the last two decades, but one that so far has been subject to limited research. Existing studies in this field have mainly focused on SA opinions, and have tried to understand the characteristics of, and the elements included in, assurance statements, instead of enquiring beyond such outputs to obtain evidence from SA providers themselves. This thesis aims to provide insights into the SA process regarding how decisions in the process are made and what could influence such decisions. It aims to understand what SA practice actually is by examining SA providers’ understandings of the meaning of the practice and the influences that such understandings have on the actual assurance process. Hence, the study focuses on the development of SA practice from the perspective of the assurance providers. It focuses on issues beyond the content of the SA statements to explore the processes leading to the actual delivery of such statements and a wide range of factors that influence the production of such statements and the development of SA practice in general. This study employs a qualitative research approach, using semi-structure interviews as the main data collection method supplemented by various textual data sources. Research participants are SA providers in the UK, including accounting and non-accounting assurance providers. Drawing on the perspective of actor-network theory (ANT), the thesis focuses on the associations involving both human (e.g. assurance providers, reporting organisations, and stakeholders) and non-human (e.g. reporting guidelines, and assurance standards) elements shaping the assurance practice. The theoretical framework based on ANT allows the flexibility in exploring important issues by following the actors, their associations, and their influence on the practice. The findings show that assurance providers’ understandings of the assurance practice vary significantly and that such variation has a major effect on how the assurance practice is conducted. The assurance providers may perceive their roles as independent assurance providers but also adopt other roles to match with the interests and demands of various constituencies. The study shows, in particular, that the providers’ perceived roles vary between what can be termed an ‘independent verifier’, a ‘sustainability consultant’ and a ‘sustainability promoter’, depending on the way in which they place importance on assurance- as against sustainability-related elements of the assurance process. Their different perceptions of their roles influence the internal dynamics of how assurance engagements are conducted. In particular, the study identifies four types of SA engagements, namely ‘social assurance’, ‘integrated assurance’, ‘formative assurance’ and ‘compliance assurance’. Such a categorisation provides a broad-based understanding of the SA as a practice field and the degree of heterogeneity within it. This study provides methodological and empirical contributions by providing evidence on the process associated with SA practice through interviews with different types of organisations providing SA services. Moreover, basing the theoretical framework on ANT highlights the interactions between different actors as a part of the development of SA practice and offers a new perspective to explore the practice and factors influencing its development.

Sustainability assurance is on the uprising. Nowadays, more and more companies are thinking about sustainability which resulted in a growing market for sustainability assurance. The global reporting initiative (2013, p.6) defines sustainability assurance as “the use of external, independent reviews of sustainability management processes and final disclosures is intended to increase the robustness, accuracy and trustworthiness of disclosed information.”. Unlike financial auditing, sustainability assurance ismostly unregulated and there are various guidelines and frameworks issued to help the assurance provider. The lack of mandatory regulations has resulted in a fragmented assurance environment where different approaches is used by different assurance providers. This in turn has contributed to the sustainability assurance process being unknown. The uncertainty around sustainability assurance affect the usersof the assurance report, for example stakeholders’, which can find it difficult to identify, interpretand compare the results of the sustainability assurance.The purpose of this study is to contribute to the limited knowledge on sustainability assurance, by investigating the sustainability assurance from both auditors’ and non-auditors’ perspectives.To assist in fulfilling the purpose, four main themes were developed; assurance team, assurance process, assurance report and the future of sustainability assurance. To fulfill the purpose of this study, the research questions are;“What is the audit process of sustainability reports?”“What does the sustainability assurance team look like?”“What does the sustainability assurance report look like?”The result in this study suggests that the process of sustainability assurance looks different depending on the assurance provider. The findings also suggest that the assurance team almost looks the same, regardless who is the assurance provider. When it comes to the results regarding the assurance report, it is evident that there are many ways to improve theusefulness and informativeness of the report. Furthermore, the findings of this study contribute to the limited knowledge of sustainability assurance by thoroughly exploring the assurance process.

The master thesis describes financial assurance of a project, which is realized by the municipalities. The theoretical part is focused on describing basic concepts of public projects, municipalities and municipal budgets. Subsequently, the work deals with sources that can provide financial assurance. Thesis is also focused on categorization of roads and the economic evaluation of roads and highways. The practical part is devoted to the basic design of the project to local roads in the municipality Plumlov - Žárovice and then financial assurance of this construction investment project. It selects several financing options for the project and the subsequent assessment of individual options. The outcome of this work is the selection of the best possible way of financing for the proposed project.