Abstract: A posture improvement device is provided, in which a predetermined amount of tension in a belt around the wearer's waist closes a switch and activates a buzzer, vibration motor, or other indicating means in a belt buckle of said belt. Means are provided to adjust the amount of tension required to achieve said closing of said switch. By maintaining sufficient tautness in his or her abdominal and lower back muscles, the wearer can maintain the tension in the belt below the predetermined threshold level, and correspondingly maintain desired improved posture. Conversely, slouching or relaxation of said muscles closes said switch and signals the wearer to improve his or her posture.