This research work is based on my Ph.D. research work and core objective of this research is to examine the re-emergence of the Taliban in Afghanistan in 2021 and its security implications for Pakistan. It was initially believed that the rise of the Taliban would help develop an understanding of securitization and increase regional economic activity between the two countries. However, the re-emergence of the Taliban have not only encouraged Pakistani militant groups harbored in Afghanistan to resume their activities but has political and economic repercussions for Pakistan. The study’s findings reveal that after the rise of the Afghan Taliban, the militant groups based in Afghanistan, such as the Tehreek-eTaliban Pakistan (TTP), Islamic State of Khurasan (IS-K) and Baloch Liberation Army (BLA), posed significant security threats to Pakistan. The scope of the study is confined to Pakistan, particularly the Khyber Pakhtunkhwa Province. This research is qualitative and descriptive-analytical, based on both historical and current information on the subject matter derived from secondary and primary data. The secondary data was obtained from published sources. Interviews and focus group discussions were used to collect primary data using a non-probability purposive sampling technique. The qualitative data analysis answered the research questions regarding security implications for Pakistan with the rise of the Afghan Taliban. In light of the data collected from respondents, the threat of militancy appears to persist. Therefore, the implications of Afghanistan’s instability for Pakistan will require further analysis in the future.