In the past year, Banagrícola had beaten its local competitors, which are now all in foreign hands, handsomely on nearly all fronts. Of the three largest banks, it is the only one to have actually grown its asset base in the 12 months through June 2009, albeit at a meager 1%.

“We have a lot of respect for the institution we have in El Salvador,” says Bancolombia CEO Jorge Londoño, noting that most of the executive team in place at the time of the acquisition has remained.

Banagrí...