Fire investigators should never attempt to testify in any court case without proper instruction in courtroom testimony procedures. The expert witness must be aware that there is nothing illegal or unethical in receiving instruction from an attorney prior to the actual testimony. The expert witness should dress conservatively and professionally. The testimony given by the expert should follow a smooth sequence. Brief pauses may be made before answering questions and if during testimony, an objection is made, the witness should withhold any further testimony until instructed to proceed. The expert witness' primary responsibility is to always give an unbiased, clear, and factual account of the fire investigation to the jury. The testimony should be easily understandable by the jury which is usually composed of people who are unschooled in fire casualty. Expert witnesses must present themselves in a cool, calm, and efficient manner. As much attention should be paid to courtroom demeanor as was given to the tedious examination of the fire scene. Three footnotes and three references are provided.