Proficiency

Each ability covers a broad range of capabilities, including skills that a character or a monster can be proficient in. Dexterity check might reflect a character's attempt to pull off an acrobatic stunt, to palm an object, or to stay hidden. Each of these aspects of Dexterity has an associated skill: Acrobatics, Sleight of Hand, and Stealth, respectively. So a character who has proficiency in the Stealth skill is particularly good at Dexterity checks related to sneaking and hiding.

The skills related to each ability score are shown in the following list. (No skills are related to Constitution.) See an ability's description in the later sections of this section for examples of how to use a skill associated with an ability. Sometimes, the GM might ask for an ability check using a specific skill—for example, “Make a Wisdom (Perception) check.” At other times, a player might ask the GM if proficiency in a particular skill applies to a check. In either case, proficiency in a skill means an individual can add his or her proficiency bonus to ability checks that involve that skill. Without proficiency in the skill, the individual makes a normal ability check.

For example, if a character attempts to climb up a dangerous cliff, the GM might ask for a Strength (Athletics) check. If the character is proficient in Athletics, the character's proficiency bonus is added to the Strength check. If the character lacks that proficiency, he or she just makes a Strength check.

Variant Skills
Normally, your proficiency in a skill applies only to a specific kind of ability check. Proficiency in Athletics, for example, usually applies to Strength checks. In some situations, though, your proficiency might reasonably apply to a different kind of check. In such cases, the GM might ask for a check using an unusual combination of ability and skill, or you might ask your GM if you can apply a proficiency to a different check.

For example, if you have to swim from an offshore island to the mainland, your GM might call for a Constitution check to see if you have the stamina to make it that far. In this case, your GM might allow you to apply your proficiency in Athletics and ask for a Constitution (Athletics) check. So if you're proficient in Athletics, you apply your proficiency bonus to the Constitution check just as you would normally do for a Strength (Athletics) check. Similarly, when your half-orc barbarian uses a display of raw strength to intimidate an enemy, your GM might ask for a Strength (Intimidation) check, even though Intimidation is normally associated with Charisma.

Working Together
Sometimes two or more characters team up to attempt a task. The character who's leading the effort—or the one with the highest ability modifier–can make an ability check with advantage, reflecting the help provided by the other characters. In combat, this requires the Help action.A character can only provide help if the task is one that he or she could attempt alone.

For example, trying to open a lock requires proficiency with thieves' tools, so a character who lacks that proficiency can't help another character in that task. Moreover, a character can help only when two or more individuals working together would actually be productive. Some tasks, such as threading a needle, are no easier with help.