Reading the Philokalia

The Philokalia is a collection of writings by the Hesychast Fathers, whose aim is to show others the ways to true contemplation of Christ, the ways to reach to God by means of hesychasm.

The word "Philokalia" can be split in "philos" = "lover of", "friend of", and "kalos" = "good", "beautiful"; Philokalia = love of good things, beautiful things.

The Philokalia has been translated in different periods for different languages. For instance, the version which is used in the Romanian Orthodox Church was compiled by Saint Nicodemus the Agiorite and Makarios of Corinth, and first published in Venice, in 1782, and translated in Romanian by father Dumitru Staniloae, in 12 volumes, in 1947-1948. But the first ever Philokalia was compiled by Origen (second century after Christ), and named "Philokalia" by Saints Basil the Great and Gregory the Theologian.
The Slavic edition was compiled by Saint Paisius Velichikovsky, and published in Sankt Petersburg, in 1793.

The full title of the book is "Philokalia, or collection from the writings of the Holy Fathers showing us how man can be purified, enlightened and accomplished.". The goal of the writings is purifying the heart, the soul, by means of practicing the Jesus prayer of the Prayer of the heart (the same), which is the core of hesychasm; and trying to reach the state in which one can see God in the Taboric (uncreated) light.

About reading the Philokalia: the book is not a magic book, is just like any other book. Nobody stops you from reading it, as an information. You don't need the guidance of a spiritual father for reading it; instead, you need the guidance not of a mere spiritual father, but an Orthodox spiritual authority (an Elder) to start practicing what's written in it. And this thing is extremely hard for today's secularised world. Even in the Orthodox countries, this is hard, and I don't know if there are any hesychasts in the West. Anyway, for a beginner (me included, even though I'm not that far away from priesthood), the hesychasm is not recommended, as this is a direct attack on the demons, a direct fight with the demons inside our souls and outside. Only people who can take it, become hesychasts; only monks can practice hseychasm and only under guidance from an Elder. And even them might as well fail.
So you can read the Philokalia, there's no problem in that (although I wonder how many things you'll understand from the book, as I have difficulties understanding them myself). And don't even think about practicing (not even alone!!) what you read - find an Elder (hard thing itself), and then you'll talk about it.

I've read parts of the Philokalia though not the entire thing. The parts I have been able to read though have been so enlightening spiritually speaking and I do think it is a beautiful thing to read.

As Andrei said I've been told by numerous people to really be guided by an Elder with what is written therein (though living in England there is pretty much only one place I could find an Elder and even then it's the other side of the country and not exactly easy to get to).