Seniority systems provide a means to reward long-term employees, but they also create legal and practical hazards of which employers should be aware. Utilizing a seniority system may raise issues involving arbitrary employment decision and discrimination. While seniority clause are an almost universal feature of collective bargaining agreements, they may also have a place in nonunion environments. Seniority systems must be crafted formulated to avoid unfair 'bumping' in the event of a layoff.