Relting on the legislation and jurisprudence of the Republic of Croatia, the paper provides a review and analysis of legal rules regulating the terms and procedure of the employment contract's ordinary notice caused by permanent characteristics or abilities of workers. Special attention is given to judicial practice which gives answers to numerous questions that arise in practice, particularly those related to the existence of reason for such a type of employment notice. In the author's view, the legislator has justifiably allowed employers to give notice to workers who cannot perform the basic obligation of carrying out the assumed tasks; for workers' protection, the legislator has prescribed explicit rules for notice procedure and judicial protection; then, the legislator has stipulated unfeasibility of employment on other tasks when giving notice to workers which are endangered by decrease of work ability or they already have reduced work ability.