It depends on the size of the organization. If it's small you just have the CEO/founder who decides everyone's salary, if it's a big bigger you have a manager

It depends on the size of the organization. If it's small you just have the CEO/founder who decides everyone's salary, if it's a big bigger you have a manager with a margin of negociation but can always get a signoff for a bigger raise by the CEO, and when it gets really big there is a hard grid with categories, ranks within the categories, lower bounds and upper bounds.