My level is between JLPT3 and JLPT2. As is well known by this forum readers, the one thing that takes more time and effort in the Japanese learning is vocabulary. However, most textbooks are focused in grammar more than vocabulary. I am doing KO2001 (about 70% done) and I needed something to reinforce kanji-vocabulary learning. I found these 2 books pdf's , and decided to buy them. They are a good complement to KO2001. So, now , when I am tired of anki reviewing, instead of studying grammar, I am learning lots of vocab with these books.

http://www.amazon.com/Intermediate-Kanji...936&sr=8-1

http://www.amazon.com/Intermediate-Kanji...936&sr=8-2

The reviews are...interesting:
"The infamous and highly controversial "Heisig Method" uses basically this same principle, except that you attach random (unrelated) English words to each character (or radical/base character). This allows you to memorize them easily, but the English word you attach to them is absolute nonsense and may confuse and harm your ability to learn the meanings of the Kanji later (yeah, you learn the meanings in the second book of Heisig's methodology; first book is nothing but the shapes of the characters). Using the Intermediate Kanji Book series (or the Basic Kanji Book series), you can do the same thing without the messy, nonsense English attached. "

Go ahead and buy what works for you!
頑張ってください！

I used IKB 1 and 2, I think it's a good series. It's a very tough step up from Basic Kanji Book but if you've got other sources it's good.

Whoever wrote that review should be murdered....... :-p

Don't listen to that review, on the contrary, this book complements RTK and KO2001.
With RTK you learn how to identify and write the kanji, then with KO2001 you learn the readings of the 1100 more usual kanji, and some vocab (around 3k). Now, we need the build vocabulary. At this stage we can skip volumes I and II of Basic Kanji Book, and go directly for the Intermediate (also 2 volumes). These books are like workbooks, with plenty of exercises to reinforce the relation between kanji, constantly comparing similar words. Check the pdf.

I'm in the middle of using IKB 1 for a JLPT prep class while doing KO Book2 at the same time... my brain hurts. IKB is definitely a step up from the BKB 1 and 2. Some useful stuff in it. Contains a lot of vocab and exercises that I haven't come across in KO. Maybe it's just because I haven't gotten far enough in KO, or ... who knows? Either way, the exercises are useful, and my vocab feels like it's expanding. (My deck definitely is.)

Not too sure I'm thrilled with it as a primary way of learning kanji, though. In fact, I ran back to KO Book 2 for the basics because I wasn't comfortable with that in particular. I like KO's way of "clumping" related kanji together better than IKB's method of just dumping 20-odd kanji at you. "Go look them up in the back and figure it out."

Then again, IKB is a solid vocab builder so far.