The emerging collective motions of swarms of interacting agents are a subject of great interest in application areas ranging from biology to physics and robotics. In this paper, we conduct a careful analysis of the collective dynamics of a swarm of self-propelled heterogeneous, delay-coupled agents. We show the emergence of collective motion patterns and segregation of populations of agents with different dynamic properties; both of these behaviors (pattern formation and segregation) emerge naturally in our model, which is based on self-propulsion and attractive pairwise interactions between agents. We derive the bifurcation structure for emergence of different swarming behaviors in the mean field as a function of physical parameters and verify these results through simulation.Note to Practitioners-Our research deals with understanding the emerging behaviors of groups of simple, interacting agents. The motivation for studying this subject is twofold. First, we seek an understanding of the mechanisms that govern collective motions of biological organisms in processes like wound healing, cancer growth, flocking and herding, etc. Second, we plan to apply our insights to the design of controllers for swarms of autonomous robotic agents programmed to carry out different tasks, such as area surveillance or monitoring in uncertain environments. Swarming behavior is typically modeled for groups of identical agents, under the assumption that sensing and processing times are negligibly small. We incorporate the real-world complications of: 1) finite sensing/processing time, which appears as a delay in our model of agent motion and 2) differences in the dynamical capabilities of swarming agents. We conduct a theoretical analysis of the collective motions of the swarm. We show the emergence of large-scale patterns in the swarm motion as a function of the physical parameters of the swarm, as well as segregation of the agents into separate groups where all agents in a given group have identical dynamics.