For a long while there, I was sceptical about primers. I tried both Laura Mercier and Smashbox’s offerings and was underwhelmed. I felt neither of them particularly changed my foundation enough to repurchase. This is not the case with La Roche Posay’s version, however.
This claims to reduce shine and make pores seem smaller, and I’m happy to report, that it does both! I throw little of this on, focusing on my t-zone (where I’m most concerned about shine etc) and then apply my foundation (currently still swooning over YSL’s new one).

I find my foundation goes on better, with a smoother more even coverage and stays on without become shiny throughout the day. This is what I have been looking for in a primer on beauty counters around the country, and have finally found in a pharmacy!
Effaclar Mat retails at around €17 and is worth every penny, in my opinion.
Have this and havent tried it yet, can’t wait to now!