UNLABELLED We have developed a multimedia-based laboratory course which has enabled us to eliminate the microscope and traditional microscope laboratory that have been mainstays of our histology course and histology courses at almost all institutions where histology is taught. The multimedia laboratory uses a library of histology images (approximately 24,000) stored on videodisc ( HISTOLOGY A Photographic Atlas, by S. Downing) as its microscope slide collection and accesses those images through barcode and computer interfaces. The laboratory workstations consist of a videodisc player, videodisc monitor, computer, and computer monitor. One workstation is available for every 4-students, and our students are encouraged to work together in groups of four or five. In our current set-up, the students are introduced to and instructed in the basic principles of histology using a computer program that interfaces with the videodisc images. The computer program is divided into 19 chapters (the chapters are typical of the chapters found in a normal histology textbook) and has: (1) a laboratory component that covers the material traditionally covered in the microscope laboratory, and (2) a lecture component that enables the students to evaluate their understanding of the lecture material in a non-punishing way. The laboratory section of each chapter is divided into a "MicroLab" section, an "InFo Time" section, and a "Quiz Time" section. Each of these sections interfaces with histological images stored on the videodisc. The students are encouraged to work through the "MicroLab" section of each chapter before moving on to the "InFo Time" and "Quiz Time" sections. The "MicroLab" sections introduce the students to the various tissues and organs of the body and is interfaced with the videodisc player and the histology images stored on the videodisc. These sections describe the basic histological features of the various tissues and organs and give the students access to multiple examples of what they are studying. The "InFo Time" sections bring up specific images and ask the students to think about the images. Information about the images being observed is available if the students want it and the students can flag those images that they found difficult. The Quiz Time section of the program is also interfaced with the videodisc player and provides access to a large number of histology images stored on the videodisc. The "Quiz Time" sections provide non-punishing review questions that the students can study after she has worked her way through the "MicroLab" and "InFo Time" sections. In addition to the use of a computer program to access the histology images stored on videodisc, we use barcodes that address specific images on the histology videodisc in a variety of ways to augment the students' laboratory and lecture experience. The benefits of using multimedia in place of the traditional microscope and microscope slide collection are numerous and include the speed at which specific histological images can be accessed and reviewed (when compared to finding a structure on a glass slide), a significant reduction in the amount of laboratory time needed by the student to learn the same amount of information, the ease of tutoring on a large monitor screen (when compared to trying to discuss a histological structure with a student through the eyepiece of a microscope), the encouragement of group study (which is difficult to do when a student is working 1-on-with a microscope), and the reduction of the number of faculty necessary to cover a typical histology laboratory session. The use of barcodes that address specific videodisc histology images has greatly changed our examination procedures and has significantly expanded the usefulness of the traditional lecture note handouts given to our students.