i work for sephora and i have to say i am surprised by some of the comments in here.
i will admit that there are both pro's and con's to working there. if you are someone who enjoys makeup as a hobby, is good at applying it, and is willing to learn A LOT about makeup, then it is a good job to have. however, the first thing i learned when i started working there is that you are expected to be a sales person, not a makeup artist.
infact, out of all of my coworkers, i am the only one who actually wants to pursue a career in makeup artistry. everyone else is going to school for various things that have nothing to do with the beauty industry, or they have families so they just work there as something to do to buy groceries. so if you are interested in the artistic realm of makeup, and you actually want to make a career out of it, it can be frustrating to work there.
the great thing is that you get TONS of knowledge and experience. you literally get trained atleast once a week, usually more. you have access to some amazing brands. you get more gratis (free stuff) than you will know what to do with. and for what the job entails, you get paid well.
sephora used to be very strict and by-the-books, but like any job, it all depends on management. we very recently updated our dress code so that we now allow tattoos, facial piercings, and unnatural hair colors, so it's pretty laid back now.
all in all, it's definitely my favorite job so far and it is a lot easier to get a job there than at mac / estee lauder. it's a great job to use as a stepping stone because you gain a lot of experience and knowledge in the beauty industry.
EDIT: oh! i forgot to add that the company is very geographically-influenced. i moved from a store in massachusetts to a store in tampa, fl. and it's like two different worlds. and i know in the new york city stores it is VERY hard to get a job there if you're not a skilled makeup artist. even the beauty school students can barely get hired as seasonal cashiers there.