Iseya is often ranked the number one hotspot of Kichijoji in magazines introducing the area and rightly deserves to be so. The food is great, the atmosphere is fun, and the price is right.
As you approach the place (I hesitate to call it a restaurant -- the word is too upscale for Iseya), even from a distance you cannot avoid noticing the huge white smoke billowing out and hearing the excitement from within. If you visit the Park location, the shabby building facing the park seems like it has been there for ages. The stairs are crooked and incredibly steep, the glass is permanently clouded, and overall, it's just surprising it hasn't burnt down already. The main location has recently been completely rebuilt and has lost its signature characteristic, its oldness, but even in its new form, it continues to offer an exhilerating experience.
At both locations, you see sweaty men turning yakitori sticks in the blazing heat of their grills. Waiters and waitresses are constantly running around catching and delivering people's orders. The customers themselves are all over the place from being completely inebriated. Don't come here for a quiet meal.
The yakitori is 80 yen a stick. The meat comes from all over the chicken and sometimes not even from the chicken at all. Names even unfamilar to Japanese people dot the menu - gatsu, shiro, kashira to name a few (these correspond to stomach, ???, and head). I personally recommend their hatsu (heart) and tan (tongue). The usual kawa (skin), tsukune (meatball), nankotsu (cartillage), and such are also very good. The giant shumai ("tedukuri shumai") is the best shumai I have ever eaten in the whole world.
After having eaten 10 sticks, a couple beers, a bowl of rice, and shared a plate of shumai, the bill almost never hits 2000 yen. I always stagger out wobbling from the alcohol and carrying my very heavy stomach. I can hardly stay away from this place for more than a week!