Employee's unauthorized travel abroad during sick leave justified immediate contract termination under Polish Labor Code.

The Supreme Court dismissed the employee's cassation appeal seeking reinstatement and back pay after his employer terminated his contract without notice. The court found that the employee, while on sick leave, traveled to the Vatican without employer consent or authorization, violating his duty to follow medical advice and subordinate orders. Consequently, the court ruled that this conduct constituted a serious breach of fundamental employee obligations, validating the employer's right to terminate the employment agreement immediately.