Just like any other process, vaccine manufacturing procedures are defined as a series of interrelated functions and activities using a variety of specified actions and equipment designed to produce a defined product. To assure the reproducibility and consistency of such processes, they must be carried out using validated equipment and under the established procedures that meet all the acceptance criteria, at least 3 times. In many cases, “worst case” conditions are used for the validation purposes to ensure that the process would be acceptable in extreme cases. Therefore, the validation concept in vaccine production facilities is a key element of the quality assurance goals which may reduce the dependence upon intensive in-process and finished products testing. Nevertheless, the concept of validation has expanded through the years to embrace a wide range of activities such as analytical methods used for quality control of drugs, the computerized systems for the clinical trials, the labeling and the process control. To perform such validation activities properly, the updated knowledge of the current regulations are needed. Therefore, the present article focuses on the recommendations in the related guidelines addressing different aspects of validation procedures related to the vaccine production facilities as a part of the product’s life-cycle.