Final answer:
Before a venipuncture, the phlebotomist must obtain the patient's informed consent, which involves the patient being fully informed of the procedure and its risks before agreeing to participate.
Step-by-step explanation:
Prior to performing a venipuncture, the phlebotomist must explain the procedure and obtain the patient's informed consent. Informed consent is a process by which a patient is thoroughly informed about the aspects of the procedure they will undergo, including potential risks and benefits, ensuring that the patient's participation is voluntary and that they understand they may withdraw at any time. This consent is typically documented with the patient's signature. In the context of medical procedures, such as venipuncture, informed consent helps protect patient rights and ensures ethical practice.