Summary
As Overseer, it’s up to you to ensure your Vault’s success. At least, that’s the premise ofFallout Shelter. But does it really all fall on your shoulders? After all, a Vault is only as good as the dwellers who are living in it.
Which is to say, your dwellers will have to strengthen their S.P.E.C.I.A.L. skills to be of the best use to you, and your Vault as a whole. However, not all S.P.E.C.I.A.L. skills are created equal. Some will be more beneficial than others, especially when it comes to the function of some of your most important rooms.

This list rates the S.P.E.C.I.A.L. skills purely by what they can aid with inside of your Vault, not while out in the Wasteland.
7Charisma
Some rooms will function better when dwellers have a high Charisma stat. This is true of every one of the S.P.E.C.I.A.L. stats, though. The way Charisma functions in your Vault is more like the icing on the cake; it is a wonderful extra to have, but it is not necessary.
Aside from the living quarters, the rooms that are made better by Charisma are the radio station and barbershop. The radio station will call dwellers from the wasteland, and the barbershop is purely about hairstyles. You could continue to expand your populationby having your dwellers become pregnant, which works faster with higher Charisma, but is not needed to, uh, get the job done.

All the S.P.E.C.I.A.L. skills can be raised in their corresponding training rooms. Once you’ve unlocked them, you may build as many of these rooms as you’d like.
6Luck
Luck may not sound like an impressive skill to have, but it has some major benefits for your Vault dwellers. But, much like Charisma, you can make it without a high Luck. You just may find yourself strapped for caps.
As it relates to running your Vault, Luck will increase the chances any Rush performed is successful. It will also impacthow many caps you makefrom any Rush or collecting resources, as well as how much of a resource you collect. So, it is helpful, yes, but it doesn’t make or break your Vault.

A Rush is an action you’re able to perform where you make a resource-producing room rush their task to quickly output more power, water, food, Stimpaks, or RadAways. If you succeed, you instantly get more of that resource. If you fail, an incident will take place in that room.
5Intelligence
Intelligence is the skill that makes the Stimpaks and RadAways go ‘round. It is the skill that helps power your Medbays and Science Labs. And, even if you never send any dwellers into the Wasteland, you’ll want to have a stock of those items ready.
Why?Incidents happen in the Vault, which means your dwellers can be injured or suffer from radiation. So, while there will be times you have a surplus of these items, you’ll need them when things are looking grim. Unless you want your dwellers to die, that is.

4Agility
A dweller has to eat, even if it would be so much more efficient if they didn’t need things like food or water. Greedy little-oh, nevermind. If you want to keep your dwellers fed, you’ll have to be sure any that are working in the diners or gardens of your Vault have a high Agility.
The higher their Agility, the faster your dwellers can provide food to your Vault and its population. If there’s a lack of food, they will begin to starve or lose HP. So long as there is enough food, not only will dwellers stay healthy, but they will heal over time from any emergencies that have happened.

3Perception
Perception is used for water production and is the skill that powersthe water treatment and water purification rooms. If these rooms fail to produce enough water, your dwellers will suffer radiation poisoning. Yikes!
That means it’s important to raise the Perception of any dwellers you have stationed in these rooms. The higher the perception, the faster they will be able to provide clean water to the whole Vault.

2Endurance
Endurance has two major benefits. One of those is that the higher a dweller’s Endurance is, the higher their HP will be. This is helpful in the defense of your Vault. The second benefit is that this skill is used for the Nuka-Cola Bottler rooms, the last room you unlock in Fallout Shelter.
This is a bit of an end-game skill, so to speak, since it is the most useful in the last room you unlock. However, it is always a useful skill to have, thanks to the impact it has on your dwellers’ HP. So when in doubt, max your Endurance out!

1Strength
Something you can’t run out of is power. If you do, parts of your Vault will go offline, meaning your dwellers won’t be able to work. And we all know that, like cockroaches, capitalism will survive even in the darkest corners of your Vault, demanding your little worker bees keep producing resources and caps. Or…would Vaults be considered to be communist spaces? Hm.
Either way, you need power. And the stat for that is Strength. Having dwellers with a high Strength stat will ensureyour power plants and power reactorsstay online and producing the electricity needed to keep everything running.