In dialogue, you can sometimes choose to Bribe someone. The Bribe option displays the amount of gold needed to successfully bribe the other character; if you can pay the price, the bribe succeeds.
The price of a bribe is based on your level and Speech skill. At higher levels, bribes become increasingly expensive, although a high Speech skill can offset this.
In dialogue, you can sometimes choose to Persuade someone. Your success at using the Persuade option depends on your Speech skill.
Some articles of apparel help in dialogue situations: