Purpose: Alteration labour, additional labour and retiring labour are the sort of extra work that the contractor can add in addition to the original order. The management of this type of construction work have comprehensive variation from project to project. This sort of work provides changes in both labour hours and project costs. In other words, a high amount of these will increase the project costs. The goal with this thesis is to identify the success factors that contributes to better management process of alteration labour, additional labour and retiring labour for renovation and redevelopment projects.  Method: This thesis has been made with qualitative research. Literature study, document analysis and semi structured interviews are the methods that have been used. The literature study provided insight in the already available research in this area. The document analysis gave understanding of the company and comprehension regarding the amount of alteration labour, additional labour and retiring labour for each project. Lastly the interviews provided profound knowledge to how the employees at Skanska Direkt manage their handling process, and which type of improvements they thought will make positive change.  Findings: The thesis has resulted in clear and concrete factors that contribute to the management process for alteration labour, additional labour and retiring labour. There have not been presented any new methods for this, however the success factors have been brought to light. Both the empiricism and theory show that a symbiosis between the design, the number of crewmembers, documentation and registration, the cooperation with the client and the possibility for the co-workers to understand and know the project is of most importance. Implications: By implementing the success factors presented in this report the amount of alteration labour, additional labour and retiring labour can be reduced. The labour that anyway emerge can be handled in a smarter and more efficient ways. The implications of this actions will for instance result in lower personnel costs, gainful cooperation’s between contractors and client, less risk for penalty expenses connected to delays. And no more than a successful company.  Limitations: The thesis only contains research including four different projects. There has been no comparison between new construction and redevelopment. The research has not taken the clients aspects into consideration. The result of this research study will be useful for average and large construction companies focusing on renovation and redevelopment projects.  Keywords: Alteration labour, additional labour, retiring labour, turnkey contract, general contract, renovation, redevelopment, project planning, construction documents, cooperation.

Att det förekommer ändringar vid utförandet av ett byggprojekt är inte något nytt i byggbranschen, utan snarare något som alltid har funnits och förmodligen alltid kommer att finnas. Ändringar som uppstår vid utförandet av ett byggprojekt kan orsakas av en mängd olika anledningar. Men det ändringarna har gemensamt, är att de i regel resulterar i något som inom byggbranschen brukar benämnas ÄTA-arbeten. Begreppet ÄTA-arbeten står för Ändringsarbeten, Tilläggsarbeten samt Avgående arbeten och är ett resultat av ändringar i ett ursprungligt kontrakt.I utförandeentreprenader gäller i regel standardavtalet AB 04, vilket är ett avtal som innefattar bestämmelser som reglerar både beställares och entreprenörers förpliktelser gentemot varandra. Standardavtalet AB 04 reglerar i den meningen även hur ÄTA-arbeten ska hanteras, för att en entreprenör ska kunna erhålla ersättning för arbeten som inte omfattas av det ursprungliga kontraktet.Den här studien inleds med att beskriva hur ÄTA-arbeten ska hanteras enligt standardavtalet AB 04. För att i ett senare skede kunna avgöra vilka vardagliga hanteringssätt som strider mot bestämmelserna och av den anledningen medför rättsliga påföljder.För att kunna ta reda på hur ÄTA-arbeten hanteras i dagsläget, utfördes ett antal intervjuer med verksamma personer inom anläggningsbranschen. Intervjuerna resulterade i en slutsats som tyder att det vardagligt förekommer hanteringssätt som strider mot bestämmelserna i AB 04, vilket i sin tur är anledningen till att entreprenörer i en relativt vid utsträckning går miste om ersättning för utförda ÄTA-arbeten. Studien ger även förslag på hur parterna kan förbättra hanteringen av dessa arbeten samtidigt som samhällsnyttiga perspektiv tas i beaktande. / The fact that changes occur at the performance of a construction project is not a new phenomenon in the construction industry, it´s rather something that has always existed and will likely do so in the future. Changes that occur during the performance of a construction project can be caused by a variety of reasons, but what those changes have in common is that they in general result in amendments of the original contract.In Swedish performance contracts the standard agreement AB 04 is regularly used, which is an agreement that includes the both parties’ obligations in relation to each other. The standard agreement AB 04 regulates in that sense even the way in how the changes shall be dealt with, in order to let the contractor be able to obtain compensation for those additional implementations. This study begins by describing how changes should be handled according to the standard agreement AB 04, in order to determine which daily doings by the contractor is inconsistent with the provisions in AB 04 and consequently leads to legal sanctions.To find out how changes are handled in current construction projects, the study conducts a number of interviews with persons that are active in the construction industry.The study resulted in a finding that puts forward that it´s fairly common that changes are handled in a manner that is inconsistent with the provisions of AB 04.The study provides also a number of suggestions on how the parties can improve the management of these changes that also takes socially useful perspective into account.