Hidden objectives - Successfully complete the indicated task during the listed mission:

American missions

1. Battle Of The Eastern Solomons: Sink every Japanese ship in the area.
2. Battle Of Cape Esperance: Eliminate the southern escaping convoy.
3. Battle Of Santa Cruz: Sink a battleship from the Vanguard Force. Additionally, destroy all enemy ships on the Veteran difficulty (hidden objective).
4. Defense Of Henderson Field: Eliminate the destroyers Ikachuki and Inazuma.
5. First Battle Of Guadalcanal: Sink the Heiei within five minutes.
6. Second Battle Of Guadalcanal: Destroy all three seaplanes stationed at Savo Island.
7. Invasion Of Tarawa: Destroy all anti-air guns.
8. Battle Of The Philippine Sea: Achieve victory without the loss of USS Albacore.
9. Divine Winds Of Leyte: Bomb all fortresses into the ground.
10. Battle Of Cape England: Destroy the Japanese transport convoy.
11. Sub On Patrol: Steal the Japanese recon plane.
12. Air Raid Against Indochina: Sink the convoy before it can escape. Additionally, destroy the train with the exploding refinery (hidden objective).
13. Invading Iwo Jima: Protect all transport ships.
14. Battle Of Okinawa: Prevent the Yamato from reaching the shore.

Japanese missions

1. Attack On Pearl Harbor: Bomb the Neosho as it passes the California. Additionally, destroy both Henry's ship and Donald's plane in Pearl Harbor (hidden objective).
2. Destruction Of Z Force: Destroy the Repulse before the reinforcements arrive.
3. Battle Of Java Sea: Prevent all the attacks on transports by sinking the destroyer Electra.
4. Saving The Soho: Find and destroy the radar station.
5. Invading Of Port Moresby: Keep hold of your bases.
6. Hunt For The USS Hornet: Destroy all transport ships in the convoy.
7. Invasion Of Midway: Disable the airfields by destroying all the fuel tanks.
8. Defense Of Guadalcanal: Do not allow any of the landing ships to reach the shore.
9. Solomons Skirmish: Keep all Japanese battleships operational.
10. Attack On Sydney's Harbour: Find the lost Japanese recon plane marked on the map as O-804.
11. Seizing The Fijis: Spot the minefield with a recon plane.
12. Meet The Germans: Sink at least one ship with both submarines. Additionally, land in the sea with a flying boat or a seaplane (hidden objective).
13. The Road To Hawaii: Destroy the radio station and its defenses on the small island to the west.
14. Invasion Of Hawaii: Send a recon plane to spot enemy submarines before the attack.

Bonus units - Successfully complete the indicated task to unlock the corresponding unit:

American missions

Allen M. Sumner Class Destroyer: Successfully complete the "Battle Of Santa Cruz" mission.
Anti-Submarine Warfare Fletcher Class Destroyer: Successfully complete the "Battle Of Cape Engano" mission.
Atlanta Class Anti-Aircraft Cruiser: Successfully complete the "Battle Of Cape Esperance" mission.
B-29 SuperFortress Heavy Bomber: Successfully complete the "Air Raid Against Indochina" mission.
Gato Class Attack Submarine: Successfully complete the "Defense Of Henderson Airfield" mission.
Iowa Class Battleship: Get a gold medal on the "First Battle Of Guadalcanal" mission.
TBM-3 General Motors Avenger: Get a gold medal on the "Battle Of Okinawa" mission.

Japanese missions

Akizuki Class Anti-Air Destroyer: Get a silver medal on the "Saving The Shoho" mission.
H8K Emily Flying Boat: Get a silver medal on the "Destruction Of Z Force" mission.
I-400 Submarine: Get a silver medal on the "Hunt For The USS Hornet" mission.
J7W Shinden Fighter Plane: Get a silver medal on the "Invading Of Port Moresby" mission.
Betty with Ohka Suicide Rocket Plane: Get a gold medal on the "Invasion Of Hawaii" mission.
Shimikazi Advanced Torpedo Destroyer: Get a silver medal on the "Solomons Skirmish" mission.
Tone Class Heavy Cruiser: Get a silver medal on the "Battle Of Java Sea" mission.
Type B Submarine with Kaiten Manned Torpedoes: Get a silver medal on the "Attack On Sydney's Harbour" mission.
Yamato Class Battleship: Get a gold medal on the "Invasion Of Midway" mission.

Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Tin Can Captain (15 points): Sink 20 enemy ships with your destroyer by using torpedoes.
Broadside Kill (15 points): Sink an enemy ship with your cruiser in 15 seconds.
Long-range Gunnery (15 points): Destroy an enemy ship which is over 2800 meters away using a battleship.
Flat-top Commander (15 points): Send 50 planes into the air with the support manager.
Death from Below (15 points): Sink an enemy battleship with your submarine.
Fighter Ace (15 points): Destroy 5 enemy planes in less than 30 seconds without losing your fighter plane.
Hat-trick (15 points): Achieve 3 torpedo hits with the same torpedo bomber.
Deadly Accuracy (15 points): Cause 20 magazine explosions with dive bombers.
Double Whammy (15 points): Damage at least two targets in one bombing run.
Supply Line (5 points): Use the support manager to successfully send up a plane or request a ship.
Advantage (5 points): Use the naval supply manager to activate a naval supply.
Banzaaai! (15 points): Crash into an enemy ship while flying at least 600km/h.
Surprise Attack (10 points): Strafe all parked planes in Pearl Harbor.
Turning Point (10 points): Sink all US Carriers in the Invasion of Midway.
Preventive Strike (10 points): Sink the US Battleship before the reinforcements arrive in Solomons' Skirmish.
Under Cover of Darkness (10 points): Win a night battle.
Queen Sacrifice (10 points): Sink the abandoned Hornet in the Battle of Santa Cruz.
Marianas Turkey Shoot (10 points): Destroy 20 enemy planes in the Battle of the Philippine Sea.
Zero Damage (10 points): None of the kamikaze planes should hit any of your ships during Divine Winds of Leyte.
Take No Prisoners (50 points): Destroy every hostile unit in Battle of Santa Cruz on Veteran difficulty.
National Veteran (20 points): Participate in 25 online sessions as the US.
National Hero (50 points): Participate in 100 online sessions as the US.
Fist of the Empire (20 points): Participate in 25 online sessions as the Japanese.
Wrath of the Empire (50 points): Participate in 100 online sessions as the Japanese.
War Room (10 points): Host and play through 50 online sessions.
Conqueror (20 points): Win 50 online sessions.
Armchair Admiral (10 points): Win an online Island Capture session using the map screen only to attack units or emplacements.
Frontline Admiral (10 points): Win an online Island Capture session without switching to the map screen.
Rising Sun (60 points): Complete the Japanese Campaign on Veteran difficulty.
Stars and Stripes (60 points): Complete the US Campaign on Veteran difficulty.
Submarine Hunter-killer (20 points): Destroy an enemy submarine with a submarine by using torpedoes.
Overwhelming Force (25 points): Complete the Japanese Campaign on Any difficulty.
Shock and Awe (25 points): Complete the US Campaign on Any difficulty.
Island Hopping (30 points): Win every Island Capture map at least once.
Victory Rush (30 points): Win every Competitive, Duel, Escort and Siege map at least once.
Fleet Commander (50 points): Reach the rank of Lieutenant.
Head of the Fleet (100 points): Reach the rank of Fleet Admiral.
Disembarkation (5 points): Capture a base by using landing ships.
Airborne Invasion (10 points): Capture a base by using paratroopers.
Don't Mess with the Big Boys (10 points): Sink a hostile carrier with your battleship.
Repair for your Life (10 points): Survive being fatally damaged by retaining minimal health.
Against the Odds (10 points): Sink a stronger enemy ship than your ship.
We're not finished yet! (20 points): Sink an enemy ship while your ship is under 3% health.
Pure Gold (10 points): Get your first gold medal.
Hero of Midway (10 points): Played Battlestations Midway.

Additionally, there are five secret achievements:

Past Memories (10 points): Destroy both Henry's ship and Donald's plane in Pearl Harbor.
I've Changed My Mind (10 points): Land manually on an airfield or carrier with a kamikaze squadron.
Underwater Hideout (10 points): Discover the secret underwater cave of Sydney Harbor.
Trainkiller (10 points): Destroy the train with the exploding refinery in Air raid Against Indochina.
Flying Fish (5 points): Land on the water with a seaplane or flying boat.

The following achievements require the "Carrier Battle Map Pack" bonus downloadable content:

The Protector (20 points): Protect both carriers as the Japanese in Escort mode on Map 12.
Northern Waves (30 points): Win a large map sized Island Capture mission on Map 14.
Battleship Shutout (30 points): Win 3 straight rounds without loss as the Japanese, in a battleship Duel on Map 13.
Siege of Midway (20 points): Win a Siege mission on Map 11.
The Survivalist (50 points): Win a Competitive match without losing your submarine on Map 12.