The concept of adhocism has emerged from the tendency of humans to find improvised and innovative solutions to problems encountered since prehistoric times. In the Stone Age, people effectively utilized available resources to meet basic needs such as hunting, shelter, and tool development. During the Roman Empire, engineers and architects constructed aqueducts, roads, and public buildings using existing materials and techniques. In the Middle Ages, rapid and practical solutions were developed for the construction of castles and fortifications. The Renaissance period emphasized the importance of improvisation and creative solutions in art and science. The modernist period, characterized by industrialization, focused on standardization and the search for universal solutions. Nevertheless, many innovative engineers and designers produced quick and practical solutions based on the principles of adhocism during this period. Charles Jencks and Nathan Silver laid the theoretical foundations of adhocism with their book "Adhocism: The Case for Improvisation" published in 1972. The book proposes flexible, local, and creative solutions against the universal and rigid solutions of modernist architecture. Today, adhocism is applied not only in architecture and design but also in social sciences, urban planning, and management sciences. Flexible and adaptive solutions provide effective responses to the problems faced by individuals and communities in a rapidly changing world. The purpose of this article is to examine Charles Jencks and Nathan Silver's book "Adhocism: The Case for Improvisation" by exploring the historical development, fundamental principles, and applications of the concept of adhocism in various disciplines. Adhocism is defined as an approach aimed at producing temporary and creative solutions, representing a transition between modernism and postmodernism. The article emphasizes how adhocism is utilized in architecture and design, highlighting its potential for providing flexible and innovative solutions.