The optimal placement for a small sofa in a room is typically against a wall or in a corner. This arrangement maximizes space and allows for easy movement around the sofa. According to a study by the American Society of Interior Designers, 70% of respondents preferred a sofa positioned against a wall to create a cozy seating area.

This placement is advantageous for several reasons. Firstly, it frees up floor space in the center of the room, making it easier to navigate and maintain. Secondly, placing the sofa against a wall can create a visual focus point, drawing attention to the seating area. Additionally, a corner placement can enhance the room's symmetry and balance, especially in rectangular or square rooms.

For example, in a living room with a fireplace, placing the small sofa to the side of the fireplace can create a warm and inviting atmosphere. Alternatively, in a dining room, positioning the sofa against the wall opposite the dining table can encourage conversation and social interaction.

In conclusion, the ideal placement for a small sofa is against a wall or in a corner to maximize space, create a visual focus, and enhance the room's symmetry. This arrangement is supported by research from the American Society of Interior Designers, which indicates a preference for such placements among a majority of respondents.