This paper deals with practices and rules of evidence that were developed to assist courts in detecting faulty recollection and to safeguard the accuracy of testimony by testing the reliability of memory. Present memory, of whatever extent and quality, initially admissible, and is then subject to impressionistic tests or rule of thumb indices of its adequacy. Examination of memory processes is most usually directed to collateral matters and not to the process by which memory takes place. A free-ranging examination of memory production in relation to any events in any context is permitted, subject to the discretion of the court. Impeachment of the witness for failure of memory under any of the aforementioned tests is a matter of impression. The legal and courtroom consideration of memory is not restricted to absolute and unaided present recollection to be reflected in offered testimony. A person's past memory, duly recorded, is also admissible in evidence. It is presumed that there is an inverse relationship between the recollection of an event and the time of its occurrence. In general, however, a substantial psychological scope attaches to the evidence rules and practices governing the present and past memory of witnesses. The tracing of the stimulus to the memory event, testing the process of association, may offer some assurance of the proper functioning of memory and of a reliable product.