If a substituent is a good electron donor, does that mean that the benzene ring is more reactive and willing to accept another substituent? (Yes, but only toward the SEAr reaction - GS). I think I am getting the para-ortho/ meta-directing groups mixed up with what a good activating and deactivating group is. How are these related? (Substituents are meta-directors only if have no electrondonating effects at all. All other substituents a o-,p-directors. Activating substituents are overall donors and deactivating substituents are overall acceptors. The resonance effect takes precedence over the hyperconjugative effect, which takes precedence over the inductive effect except for halogens, which are deactivating substituents. To avoid the most common mistake, consider the existing substituent, not the incoming one. - GS)