Upping a Caster's Concentration Bonus

[arangatang]

How can one increase a caster's concentration bonus?

[Glimbur]

Increase your Con. This is good for other reasons too.

A Tunic of Steady Spellcasting from MiC or Complete Arcane.

Skill Focus: Concentration. But feats are expensive.

By mid levels, you should be able to constantly hit the DC for defensive casting so I assume this is low level advice, in which case metamagic is less applicable so Skill Focus is a legit move if it's a short campaign or retraining is allowed.

[Volos]

Steadying Robe from Complete Mage so that you can cast mounted without being bothered by movement.

Mounted Combat & Mounted Casting (Miniatures Handbook) for +10 to Concentration checks while mounted.

Now you have a +10 untyped bonus to Concentration and you have the same base DC for casting as if you were on the ground. You can have the mount move for you, leaving you open to do more and getting you out of tight spots faster. Combind this with whatever else you like/need to get a huge bonus to Concentration checks.

[bartman]

There are several items in the MIC that give a bonus to Concentration

Circlet of Mages, 5000gp, +2, page 86, Head slot
Third Eye Concentrate, 10000 gp, +10, page 141, Face slot
3 pieces of Seven Veils collection, +2 bonus, price varies, body slots varies, page 211
Tunic of steady spellcasting, 2500 gp, +5 bonus, page 144, Torso slot

You could also follow the DMG fora custom magic item, cost is bonus squared * 100gp, ie: +1 = 100gp, +2 = 400gp, +3 = 900gp, etc. this is of course if your DM allows custom magic items

EDIT: wow, ninja'd hardcore. I have to start writing my posts up in notepad first, then copy-paste when im ready

[Dr.Epic]

I believe there are two feats that can do this. One's skill focus, the other I forget the name. I think also if you cast defensively you get a bonus but that may be only with the other feat whose name I can't remember.

[Claudius Maximus]

Combat Casting, which stacks with Skill Focus.

[Yorrin]

Races of Stone has a feat that requires Combat Casting, shield proficiency, and like... 5? ranks in Concentration, but makes it so none of your spells provoke AOs as long as you're wielding a shield. Nice if you're a divine caster or if you've got some other way to conveniently wield a shield.

[Greenish]

Races of Stone has a feat that requires Combat Casting, shield proficiency, and like... 5? ranks in Concentration, but makes it so none of your spells provoke AOs as long as you're wielding a shield. Nice if you're a divine caster or if you've got some other way to conveniently wield a shield.Like mithral light shield or buckler. 0% ASF, 0 ACP.

Remember to equip it with wand chamber, shield sheath and later enchant it with Warning.

[Runestar]

One of the familiars gives +3 concentration check. Elven wizard3 doubles that to +6.

Not technically increasing, but steady concentration (RoS) lets you take 10 on concentration checks.

How high a check are we looking at?

[Darrin]

Shape Soulmeld: Vitality Belt. +4 morale bonus on all Constitution-based checks.

Githcraft armor/shields. +600 GP, and each item adds a +1 untyped bonus to Concentration checks. A chain shirt + dastana + chahar-aina + 2 bucklers = +5 bonus.

Marshall hireling/cohort + Motivate Constitution adds the Marshall's Cha bonus to all your Constitution-based checks.

Draconic Aura feat/Dragon Shaman, Stamina Aura adds at least +1 to Concentration checks.

[FlyMolo]

If you're a charisma-based caster, becoming a necropolitan costs you 1000 xp plus a level, but allows your charisma bonus to concentration because you're undead. That's pretty nice, and doesn't mess with anything else in this thread. Being undead is also pretty nice.

Edit@V
Elan Psion with augmented elemental psicrystal and crawling tattoos. He was my arena character!

[Psyren]

If you're a charisma-based caster, becoming a necropolitan costs you 1000 xp plus a level, but allows your charisma bonus to concentration because you're undead. That's pretty nice, and doesn't mess with anything else in this thread. Being undead is also pretty nice.

Tangential to the thread, but I LOVE your avatar... is it a specific class?

I'll contribute to the thread - if you are somehow psionic (say a psionic race or template), you can expend your focus to "Take 15" on any concentration check. This applies to any concentration check, even if you're using it to cast spells rather than manifest powers.

[dgnslyr]

Masterwork Item of Concentration, maybe? What WOULD a Masterwork Item of Concentration look like?