The thing about a perfect espresso is finding not just the perfect demi-tasse of heavenly black ambrosia, but in an ideal world, finding the perfect place to drink it. My own prejudice is for a pavement cafe in the summer heat, preferably sitting in the shade, where I can watch the world go by while I sip my coffee and reflect upon Life, the Universe and Everything. Obviously looking for summer heat as well makes finding the perfect espresso a short-season activity here in Ireland at the best of times, but a good espresso is a great reviver and so is worth the hunt. In recent years there's been something of a coffee boom in Ireland with more and more eating places offering good coffee and no doubt Starbuck's will be arriving soon enough.

It's probably a good idea to avoid anything that calls itself an 'expresso', after all if they can't take the trouble to spell it right what hope do you have? The question however, is to define what a good espresso is and my criteria to answer it are these:

1. It should be made from a good blend of coffee. Dark, strong and not bitter. The roaster's skill is in making a dark roast without making the resultant beans bitter to the taste.

2. It should not be watery. This defeats the whole idea of an espresso, which should be concentrated, strongly flavoured, and with enough caffeine to give an elephant with sleeping sickness a kick-start. Between a third and a half of a demi-tasse is about right, anything more than that I'd call 'long'.

3. The crema. I use the Italian word for want of an English one. The crema is the light brown foam on the top of a wellmade espresso and comes from the oils in the beans. In the perfect espresso this crema will be thick enough to support a spoonful of caster sugar briefly before it sinks and dissolves. This is a good test, because a thick crema will only be there if the blend is good, if the pressure in the machine is set just right, and if the temperature is exactly right. Too hot and the crema is dark and burnt-tasting, not hot enough and it's pale and thin. An Italian would no more drink an espresso with no crema than an Irishman would drink a Guinness with no head.

4. Extras. The right sugar for an espresso is caster sugar, rather than the common granulated. A glass of water is the traditional accompaniment.

People keep telling me about the new cafe society in Ireland so I thought I'd put a few well-known Dublin coffee houses to the test. Here's what I found.

Cafe Java, South Anne Street.

If the sun shone, the outdoor tables on the pavement of South Anne Street would be a lovely place to sit and watch the world go by. Cafe Java offers several types of coffee: regular, espresso, capuccino, Americano (lots of water) and various flavoured varieties in a choice of single or double. The espresso was slightly bitter and there wasn't much crema. It was served alone and cost £1.10.

The Expresso Bar, Ballsbridge.

A newly revamped restaurant/bar where the old Dublin institution of Cora's used to be. Smart interior design, it offers the usual variety of coffees. A good blend of coffee, but the espresso had not much crema and too much water. £1.10 here too.

Pasta Fresca, Chatham Street.

Tables and chairs outside, stools around the bar inside make this a very traditional setting for an espresso. £1 even gets you an espresso with a reasonably thick crema and not too long. Good flavour and it comes with the proper sugar.

Woods of Baggot Street.

Tables both inside and out and the usual array of coffee choices. The espresso was okay, only a little crema but a good coffee blend and a good flavour. Seems that £1.10 is the going rate.

Brownes Deli and Cafe, Sandymount Green.

Feels a bit like a club here, everyone seems to know everyone else. Best of the five espressos although it came in a big pottery mug, which is hardly traditional. It passed the sugar test easily - the only one to do so - and proper sugar was on the table. Out-of-town prices meant it cost an even £1.

Ten years ago the only decent coffee I could get was at home. There's no doubt things are improving for the better. You can't really make an espresso at home despite small electrical appliances that say that they do; but you can make a good coffee. My favourite blend is Illy - expensive but worth it - and at home I use an Italian style cafetiere, the one where the water goes into the bottom and comes up through the grounds into the top. It's also known as a Moka Express. It's not as intense as an espresso made with a big high power machine, but it does make the next best thing and it's better than a bad espresso.

There's a new gadget sweeping Italy at the moment and I've no doubt it'll come here too. It's a milk creamer. You put the milk into it and heat it to about 150 degrees then with a plunger you foam the milk before turning your coffee into a cappucino. It works brilliantly and I use it every morning for that big first-thing mug that brings me to life.