YES!!!! shotokan is effective in self defense, shotokan karate is one of the best styles of karate once you know how to use it is very effective. i have had to use it in fights 5 times now and IT WORKS!!! i have been doinshotokan karate for 2 years now, i am a 2nd brown belt and i know how to use shotokan karate. to me its the best style, i wouldnt goto any other style or mix in, i want to mast this one style, the power house style of karate, shotokan karate. and for you ppl who say shotokan is slow LOL ok tell me this if shotokan is the powerhouse style of karate, i know it is, then speed equals power right, so if it is a powerfull stlye then you have to be fast to get that power, i know this. i am very fast and very pwerfull. my sensie is a 3rd black bvelt and i can put up a good challenge against him, iv had 5 bruised ribs just from sparring with him, and that was light comtact, so it is a very powerfull style and fast style.