Purpose: The purpose of this study is to investigate the different consumption attitudes of generation X & Y and their privacy concerns regards to company’s use of online behavior advertisement (hereafter referred to as OBA) Research questions: RQ1. What are the differences in consumption behavior between generations X and Y regarding the effect of OBA? RQ2. What are the differences between Generation X & Y regarding privacy concerns about OBA? Method: Due to this thesis’s purpose and research questions, a quantitative method was chosen which investigated 3 hypotheses that are used to answer the purpose and research questions. The survey was distributed through Facebook and led to the respondent group consisting of 281 respondents from both generations X & Y. The answers were analyzed by using t-tests in IBM SPSS 26. Conclusion: This thesis concluded that there is a significant difference between generation X & Y. Generation Y are less concerned about their privacy and have a more positive view of personalized content. Generation Y is more likely to click on advertisements that come up for them as well as appreciating adapted advertisements. This could explain why OBA has gained increased interest over the years from marketers and companies. The results also indicated that a majority never clear their web browser from cookies which is one of the cornerstones for OBA to work, which may indicate that both generations want customized content when using the internet and social media