Informed consent is a process where the participant understands and agree for a study or research. The informed consent process need to fulfill two main objectives which are the ethical and moral right of autonomy, freedom of choice and the legal authorization for a study. It is not only a legal and ethical obligation but a core factor in decisional process. Humans need to be treated as autonomous entities, who are carefree to conduct their lives as they choose without others to controls. Participants are treated as autonomous agents in a study if researcher has informed them about the study, giving them choice to choose whether to participate, and allowed them to refuse participating in the study at any time with no penalty (Levine, 1986). Informed consent is an important tool prior to every study using human as subjects for study. Obtaining consent involves notify the subject about important things such as introduction of study activities, statement of the study purpose, selection of research subjects, explanation of procedures, description of risk and discomforts, description of benefits, disclosure of alternatives, assurance of anonymity and confidentiality, offer to answer question, voluntary involved in the study, option to retreat and consent to incomplete disclosure for some studies. By doing so, the participation of subjects in the study is voluntary. There are several issues related to informed consent regarding research involving human subjects. There is an issue with subjects who have diminished autonomy where they are vulnerable because of legal or mental incompetence, terminally ill or confinement to an institution such as prisoners (Levigne, 1986). These subjects require additional protection of their right to self –determination because of their inability to give informed consent. Furthermore, these people are vulnerable to coercion which happen when one person intentionally present an overt threat of harm or an excessive reward to another to obtain compliance. When a study involved children under the age of 18, consent has to be obtained from parents. Often a child’s competence to give consent is operationalized by age, with incompetence being irrefutable up to age 7 (Broome, 1999). The U.S Department of Health and Human Services (DHHS) regulation require “soliciting the assent of the children and the permission of their parents or caretakers. Assent is defined as a child’s affirmative agreement to be a part of study. During a study, the children need to be given a choice to ask questions and to withdraw from study if he or she desires. Language barrier is another issue involving informed consent. Misunderstandings and misinterpret of information can happen because of incorrect or inadequate language translations. According to U.S Department of Health and Human Services regulations, to protect the human rights, it is mandatory that informed consent information be presented “in language understandable to the subject” and, in most situations, that informed consent be documented in writing. Subjects who cannot speak English must be presented with a consent document, written in a language that they understand.