I have never been late to school or to work. I understand that my absence can cause problems for other colleagues. That's why I always prefer to come to work thirty minutes before and not risk coming exactly on time, to risk traffic jams or other unexpected things. However, if something extraordinary happened, I would notify my manager as soon as possible and kindly ask him to find a replacement for me, or to somehow organize the work of other partners until I arrive. I would apologize to all my colleagues upon my arrival and start working.