Metacognition--knowledge, monitoring, and regulation of cognition--is key to learning and academic achievement. This is robustly supported for K-12 and higher education learners while empirical evidence in early childhood is encouraging but limited. To address these gaps in the literature, our first goal was to investigate early metacognition across two developmentally appropriate measures. Our second goal was to examine associations to executive function and motivation. Participants were 77 preschoolers, aged 3-5. Metacognition was measured using a metacognitive knowledge interview (declarative metacognition) and a metacognitive skills observational scale (procedural), both in the context of a problem-solving puzzle task. Executive function was assessed with the Head Toes Knees Shoulder measure and motivation was operationalized as persistence (time on task) on the puzzle. All children exhibited evidence of metacognitive knowledge and skills. Declarative and procedural metacognition were significantly and positively related to one another and to executive function and motivation, though to varying degrees. Controlling for language and age, metacognition significantly and positively predicted executive function and motivation. Metacognitive "knowledge" predicted executive function and metacognitive "skills" predicted motivation. Results contribute to psychology and education by reinforcing recent findings that metacognition develops far younger than was originally thought, and explicating relations between and providing models for assessing early metacognition, executive function, and motivation. We propose that these skills are intentionally fostered in early childhood.