It should be remembered that 'rank' is the out of character term for someone's status level. The correct term for a character's standing within a faction or guild is the title, which has been bestowed upon them.
At each rank that is attained in a faction or guild, a character gains the ability to learn a new skill from the appropriate rank skill list, provided they spend the requisite amount of OSP's. Skills brought in this way (by achieving the required prerequisite rank and, if necessary, having the appropriate basic skill_ cost less than they would, should the character attempt to learn the skill alone. This represents the greater access a character would get to methods of training and expert teaching at their new level of social standing and responsibility. See the booklet Occupational skill: A Guide to Advancement for more information on the available guild and faction skills or the OSP section for general skills.