Individualized social niches are defined as the subset of an individual's social environment that arises from interactions with conspecifics and influences the individual's inclusive fitness. This concept differs from social environments and social roles, which are broader and include more interactions. Social niches are integral to understanding how individuals interact with their social environment and how these interactions affect their fitness. The article clarifies the concept of individualized social niches and distinguishes them from related concepts such as social environments and social roles. It also introduces three processes—social niche construction, conformance, and choice (NC³ processes)—that explain how individualized social niches originate and change. These processes are crucial for understanding how individuals adapt to their social environment and how these adaptations influence their fitness. The article emphasizes the importance of considering both abiotic and biotic factors, particularly conspecific interactions, in understanding individualized social niches. It also highlights the role of social interactions in shaping individualized social niches and the importance of fitness in determining what belongs to a social niche. The article further discusses the differences between social niches and social environments, emphasizing that social niches focus on interactions that directly affect an individual's fitness. The concept of social niche construction is defined as the process by which an individual actively changes its social environment to influence its fitness. Social niche conformance is the process by which an individual adjusts its behavior in response to its social environment. Social niche choice is the process by which an individual selects a different social environment to interact with. These processes are essential for understanding how individuals adapt to their social environment and how these adaptations influence their fitness. The article also discusses the importance of empirical research in studying social niches and the need for a clear conceptual framework to guide this research. The article concludes by emphasizing the importance of understanding individualized social niches in the context of evolutionary and behavioral biology.Individualized social niches are defined as the subset of an individual's social environment that arises from interactions with conspecifics and influences the individual's inclusive fitness. This concept differs from social environments and social roles, which are broader and include more interactions. Social niches are integral to understanding how individuals interact with their social environment and how these interactions affect their fitness. The article clarifies the concept of individualized social niches and distinguishes them from related concepts such as social environments and social roles. It also introduces three processes—social niche construction, conformance, and choice (NC³ processes)—that explain how individualized social niches originate and change. These processes are crucial for understanding how individuals adapt to their social environment and how these adaptations influence their fitness. The article emphasizes the importance of considering both abiotic and biotic factors, particularly conspecific interactions, in understanding individualized social niches. It also highlights the role of social interactions in shaping individualized social niches and the importance of fitness in determining what belongs to a social niche. The article further discusses the differences between social niches and social environments, emphasizing that social niches focus on interactions that directly affect an individual's fitness. The concept of social niche construction is defined as the process by which an individual actively changes its social environment to influence its fitness. Social niche conformance is the process by which an individual adjusts its behavior in response to its social environment. Social niche choice is the process by which an individual selects a different social environment to interact with. These processes are essential for understanding how individuals adapt to their social environment and how these adaptations influence their fitness. The article also discusses the importance of empirical research in studying social niches and the need for a clear conceptual framework to guide this research. The article concludes by emphasizing the importance of understanding individualized social niches in the context of evolutionary and behavioral biology.