Felicity: Guess what I majored in. Hint - not the secretarial arts!
Oliver: Felicity! If I'm going to be Oliver Queen, CEO, the I cannot very well travel down 18 floors every time you and I need to discuss how we spend out nights.
Felicity: And I love spending the night with you...three...two...one. I worked very hard to get where I am and it wasn't so I could fetch you coffee!
Diggle: Well, it could be worse. My secret identity is his black driver.

I would have emailed, but this isn't exactly an email hot spot.

Oliver: If we're gonna do this, it has to be about Tommy. I need to be the man he hoped I could be. Now you two have helped me take the first step.
Felicity: So what's step two? I'm game for anything as long as it doesn't involve skydiving, and I'm pretty down on landmines now, too.
Oliver: The city still needs saving, but not by The Hood. Not by some vigilante who's just crossing names off a list. It needs something more.
Diggle: It needs a hero, Oliver.
Felicity: It's too bad The Hoods kind of ruined your nickname.
Oliver: No, it's good. I don't want to be called The Hood anymore.
Diggle: Okay. So what do you want to be called?

Besides, Army regulations. A brother never lets a soldier go into battle alone.

I take back every joke I made about you sticking a tracking device in your boot.

Diggle: What did you want?
Felicity: Is that any way to treat a girl who just walked up six flight of stairs?
Diggle: No, it's not. Welcome.

Oliver: Do you want Lauton arrested?
Diggle: No.

Then let's talk about Helena. Oliver, if you didn't still have feelings for this girl you would have thought of a different solution than letting her extort you into killing someone.

Felicity: Where are we going to get our hands on a rare Spanish antiquity?
Diggle: You really have no idea how rich his family is, do you?

Diggle: Oliver, if this were anybody else you'd be hooded up right now on your way to have an Arrow side chat with them.
Oliver: This isn't anybody else. This is my mother, and I know her.

Diggle: Woah. That's a neat trick. You gonna teach me that someday?
Oliver: No.

Diggle: Find what you're looking for?
Oliver: Took down three Vertigo pushers tonight, Diggle. Last one finally knew a name. The Count.
Diggle: The Count. That's worse than The Hood.

Arrow Quotes

There are people in this world who deal only in extremes. It's naive to think that anything less than extreme measures will stop them.

Amanda

Laurel: Helena, you don't have to do this.
Helena: Yes, I do. Because once you let the darkness inside, it never comes out.