While i don't disagree with what KK has written, IMO ristretto refer's to a flavour profile rather than specific millage. In one of my previous comps I got hammered in points for serving 'ristretto' shots. Even though the judges conceded that my pours were 27mls extracted in 22seconds (within the WBC guidelines for espresso), I was still marked down because of the overall flavour profile. A ristretto is a more 'wound up', and tighter flavour profile. A lot more intense and with far less distinction of flavour than a traditional espresso. There are many ways of getting to that flavour profile, but for ease of use and maintaining workflow in the cafe, if i had an order for a ristretto, I'd simply do everything the same as an espresso, except instead of leveling off straight (which is my normal practise, with grind etc to match), I updose a slight mound (approx 2mm in the center). This wouldn't work if you updose normally as you couldn't get enough coffee into the basket, and so, would have to adjust the grind. Then I'd cut the pour just as you see any change of colour (from redish brown to caramel). Usually this yields around 15-20mls. As for a lungo, yeah, your looking at 35-50mls pulled through and yes, it does make the shot taste like ass. The only reason anyone orders these is because they are a moron. Or more seriously, because it extracts more caffeine than in a standard espresso.