Through a standardized questionnaire, this study investigated the opinions and attitudes of Vaccine Service staff in the Puglia Region of Italy regarding simultaneous administration of vaccines. Co-administration was practiced by 89.4%, and the staff's positive opinions were that it is important for work organization (80.8%) and as an opportunity to increase vaccine take-up (59.9%). Negative opinions were that it increases the risk of adverse reactions or undesired effects (11.3%) and can engender fear of such reactions in parents (31.1%).