This study presents a novel mechanism for flocking in self-propelled particles, where flocking emerges from interactions that turn agents away from each other, rather than through alignment interactions. Using simulations, kinetic theory, and experiments, the researchers demonstrate that flocking can occur in self-propelled Janus colloids with stronger repulsion on the front than on the rear. The polar state is stable because particles achieve a compromise between turning away from left and right neighbors. Unlike alignment interactions, the emergence of polar order from turn-away interactions requires particle repulsion. At high concentration, repulsion produces flocking Wigner crystals. Whereas repulsion often leads to motility-induced phase separation of active particles, here it combines with turn-away torques to produce flocking. Therefore, our findings bridge the classes of aligning and non-aligning active matter. Our results could help to reconcile the observations that cells can flock despite turning away from each other via contact inhibition of locomotion. Overall, our work shows that flocking is a very robust phenomenon that arises even when the orientational interactions would seem to prevent it. Flocking, the self-organized collective motion of active agents, is ubiquitous in nature. It occurs in many systems across scales, from bird flocks to bacterial colonies and cytoskeletal filaments driven by molecular motors. Flocking is a landmark phenomenon in active matter, launched by the Vicsek model, which describes flocking through alignment interactions. However, recent work has shown that flocking can also emerge without explicit alignment interactions. Instead of aligning with neighbors, agents can experience alternative interactions, such as aligning with their own velocity or force, colliding inelastically, or chasing others in their vision cone. Such alternative interactions were inferred in schooling fish and might be more widespread than standard alignment interactions. For example, robots in a swarm might benefit from collision-avoidance interactions that reorient them away from collisions. Similarly, several types of motile cells undergo contact inhibition of locomotion, a behavior where cells repolarize away from cell-cell collisions. Yet, cell layers and trains have been observed to flock, both in simulations and experiments. How do cells flock despite interacting via contact inhibition of locomotion? More generally, what types of orientational interactions lead to flocking? Here, we show that agents that turn away from each other can collectively align and flock. This finding is surprising because turn-away interactions are intuitively expected to prevent and destroy orientational order. We show that this mechanism of flocking requires the combination of turn-away torques and repulsive forces between the particles. Therefore, our findings bridge the classes of alignment-based and repulsion-based phenomena in active matter, respectively represented by flocking and motility-induced phase separation. Our results expand the types of interactions that can produce flocking, and they might help to understand the physical origin of flocking in cell collectives. More generally, our results demonstrate the emergence of macroscopic polar order from microscopic interactionsThis study presents a novel mechanism for flocking in self-propelled particles, where flocking emerges from interactions that turn agents away from each other, rather than through alignment interactions. Using simulations, kinetic theory, and experiments, the researchers demonstrate that flocking can occur in self-propelled Janus colloids with stronger repulsion on the front than on the rear. The polar state is stable because particles achieve a compromise between turning away from left and right neighbors. Unlike alignment interactions, the emergence of polar order from turn-away interactions requires particle repulsion. At high concentration, repulsion produces flocking Wigner crystals. Whereas repulsion often leads to motility-induced phase separation of active particles, here it combines with turn-away torques to produce flocking. Therefore, our findings bridge the classes of aligning and non-aligning active matter. Our results could help to reconcile the observations that cells can flock despite turning away from each other via contact inhibition of locomotion. Overall, our work shows that flocking is a very robust phenomenon that arises even when the orientational interactions would seem to prevent it. Flocking, the self-organized collective motion of active agents, is ubiquitous in nature. It occurs in many systems across scales, from bird flocks to bacterial colonies and cytoskeletal filaments driven by molecular motors. Flocking is a landmark phenomenon in active matter, launched by the Vicsek model, which describes flocking through alignment interactions. However, recent work has shown that flocking can also emerge without explicit alignment interactions. Instead of aligning with neighbors, agents can experience alternative interactions, such as aligning with their own velocity or force, colliding inelastically, or chasing others in their vision cone. Such alternative interactions were inferred in schooling fish and might be more widespread than standard alignment interactions. For example, robots in a swarm might benefit from collision-avoidance interactions that reorient them away from collisions. Similarly, several types of motile cells undergo contact inhibition of locomotion, a behavior where cells repolarize away from cell-cell collisions. Yet, cell layers and trains have been observed to flock, both in simulations and experiments. How do cells flock despite interacting via contact inhibition of locomotion? More generally, what types of orientational interactions lead to flocking? Here, we show that agents that turn away from each other can collectively align and flock. This finding is surprising because turn-away interactions are intuitively expected to prevent and destroy orientational order. We show that this mechanism of flocking requires the combination of turn-away torques and repulsive forces between the particles. Therefore, our findings bridge the classes of alignment-based and repulsion-based phenomena in active matter, respectively represented by flocking and motility-induced phase separation. Our results expand the types of interactions that can produce flocking, and they might help to understand the physical origin of flocking in cell collectives. More generally, our results demonstrate the emergence of macroscopic polar order from microscopic interactions