Fallout: New Vegas

Location: Camp McCarran (Inside Camp McCarran Terminal Building)
Requirement: Speech 25
Person: Angela Williams
Quest given: There Stands the Grass

When you enter Camp McCarran, head to the right side and enter the Terminal Building. Head left behind the Escalator Stairs and you'll see a lab on your right. Inside the lab are two people, Thomas Hildern (who gives you There Stands the Grass quest) and Angela Williams. Speak to Thomas Hildern first and then speak to Angela Williams. Ask her what do you think of Dr. Hildern? and the Speech challenge shows. Select it then click Goodbye. Talk to her again and say I have some more questions. Click the what do think of Dr. Hildern again and repeat as many times as desired. Good for XP boosting as well.

Requires Medicine 35
After you accept the first quest (House always wins) of getting the chip to House (who is on the top floor of Lucky 38 casino), you can chat with him. There will be an option that says "Who exactly are you, Mr. House?" After that an option appears that says "You appear to be a computer, not a man."
If you have 35 medicine the speech option will pop up and you can do it and it counts for the achievement. After you do that, their are two other chat options and a lets talk about something else option. if you go through the other two chat options, the who exactly are you question will pop up again and after that so will the speech challenge. Keep doing this 50 or however many times you need to do it and the achievement will pop up.

Courtesy of: SashaQ
Requires: speech 50
there is another glitch that you can take advantage of. at camp mccarren, if your rep is "sneering punk" or "unpredictable" with the NCR, when you go to talk to Colonel Hsu as part of the No, Not Much mission or to pick up the mission I Put A Spell On You, you will have to speech challenge him (speech skill 50 required) in order for him to give you the mission. After you perform the majority of I Put A Spell On You, you are tasked with finding the bomb on the monorail and to defuse it. You can choose to speak with Colonel Hsu before you leave the building to find the monorail, and if you speak with Colonel Hsu the speech challenge will pop up again and you can talk in circles with him and continue to speech challenge him.

ATTENTION: ONE (or both) OF THE FOLLOWING 2 HAVE BEEN PATCHED, IF YOU WANT TO HELP ME FIGURE OUT WHICH ONE IT IS COMMENT, OTHERWISE I'D AVOID DOING THEM.

Courtesy of: AMC slave
Requirements: guns 25-44
During the Flags of Our Foul-Ups quest at Camp Golf. if you have a guns skill under thats at least 25 but less than 45 you can talk to Mags about doing marksman training and it requires you to pass 3 skill checks by needing 25, 35, 45. you can pass the first 2 but as long as you fail the 3rd you can continue to redo the training, passing the first two skill checks and they continue to count towards the achievement

Courtesy of: m0rph3us17
Requirements: Speech 40
Another glitch on the Flags of our Foul-Ups quest:
After getting the quest, first talk to O'Harahan and agree that the whole team needs to improve their teamwork. This requires you to convince Razz, Mags and Poindexter of this approach. Talk to Razz and find the conversation path corresponding to O'Harahan's suggestion. Convincing Razz of this approach requires a speech check of 40. However, the speech check dialogue option won't disappear once selected so you can continue to repeat it for both this achievement and experience farming.

First you need to do the mission called "The moon Comes Over The Tower" in the game. Emily Ortal comes up to you while walking onto the Lucky 38 one time and just hands you the mission, no need to search for her. The mission takes about 2 minutes to finish, really fast mission. Then turn it into her. After that, talk to her and find the speech check. You need Speech of 35. The speech check never goes away. This method can be used to get the Outstanding Orator achievement. This glitch was found by my fiancée!

**There may be some spoilers in this guide but they are only spoilers to side quests, not any main quests**

This achievement can be obtained much easier in this game than in fallout 3 because speech challenges are not limited to only the Speech skill. You will encounter many different speech challenges that will depend on your medicine, repair, explosives, speech, science, intelligence, perception and barter skills. The most common speech challenges will deal with speech, barter, and medicine skills. Also a lot of challenges will have multiple ways to coerce the person you are talking to (for example you may be able to influence them with a barter skill of 60 or a speech skill of 50). Depending on the type of character you have built, you can gain this achievement fairly easily without glitching any NPCs into talking in circles.

Some easy speech challenges to consider when grinding for this achievement:

In Goodsprings, you can pick up the mission Ghost Town Gunfight, which is about the powder gangers searching for Ringo. If you pick up the mission from Ringo (instead of Joe Cobb or Trudy) you can speech challenge him (skill level 20 required) to find out why he is in Goodsprings. With a 25 explosives skill you can get dynamite from Easy Pete. With a 25 barter skill you can convince Chet (inside the general store) to donate supplies instead of purchasing the supplies. You can convince Trudy to join with either a 25 speech skill or a 25 sneak skill. Finally you can get Dr. Mitchell to provide additional medical items if you have a medicine skill of 30.

Go to Bitter Springs (NCR territory) and pick up the mission No, Not Much from Captain Gilles. This will branch out into five more missions, and a few of them can be easily completed with some type of speech skill. These missions include: Medical Mystery/Restoring Hope (at camp forlorn hope; medicine skill 50 required); Flags of our foul ups (at camp golf; if you speak with Mags, you get three speech challenges if your gun skill is at least 45 and three more speech challenges if your explosives skill is at least 45); Climb Ev'ry Mountain (north of Bitter Springs; when you reach the target, speech skill 50 will get him to leave);

During the mission Oh, My Papa (Great Khans/Red Rock Canyon) you are asked to convince members of the Khans to speak out against Caesar &the legion. Speak with Jack and Diane in the drug lab and there are several speech challenges. If you speak with Jack and tell him you can teach him new chem recipes you will get 5 science challenges, (science skills 50 for the first 4 and 75 for the last). Also you can convince Jack that the legion will split him and Diane up with a 25 speech skill. Also during this quest if you try and remove Caesar's representative from the area, you can speak with Karl and trick him into badmouthing the Khans in front of their leader with three speech challenges (skill levels 25, 50, and 75 required). Also when you take Karl's journal to Papa Khan you receive two speech challenges (skill level 50 required).


While this guide does not provide 50 instances of speech challenges, I hope it does highlight the many different ways you can succeed at speech challenges and gives you a jump start on your required 50. If anyone has anything to add to this guide, please send me a message or leave a comment and I would happily add your suggestions and give you credit for them as well. Good luck! =)

*UPDATE/EDIT 17 May, 2011*
This conversation is updated/patched. You can talk with Dazzle and perform a Speech or a Medicine challenge only one time.
I also tried it after clearing cache and it still didn't work, but maybe that's because I'm an enemy of the Strip. I can't confirm this, because I don't have a save game before I became hostile. (Thank you puppetface for the heads up).
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Location: Courtyard in Gomorrah Casino (Othega runs the casino).
Person: Dazzle (in the middle of the Courtyard)
Requirements: Speech 35 or Medicine 35 and some Med-X

You can talk with her for a bootycall. But you don't want to pay in caps, so you convience her to do it for 1 Med-X. You can do this over and over, untill you run out of Med-X.
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This is still availible:

Some general information for other Speech challenges:

At Mick and Ralphs (in Freeside) you can buy a clothing piece, called Naughty Nightwear. This gives you +10 Speech and +1 Luck.

You can also make some Party Time Mentats at a campfire, this gives you +5 Charisma= +10 Speech.
Requirements:
Science 50, 1 Mentats, 1 Whiskey and 1 Honey Mesquite

To get this at the start of the story, use the following exploit.

When you start, make sure you have both Speech and Barter at 25 (Charisma increases these, and you can tag the individual skills to improve them further)

Step 1. Activate "Run Goodsprings Run" Quest by talking to Cobbs in Goodsprings
Step 2. Kill Ringo
Step 3. Talk to Cobbs and unlock the optional segments, such as "shake down the store for supplies"
Step 4. Kill Cobbs (and, if detected, the gangers)
Step 5. Go to the General Store (Chet)
Step 6. Tell him the powder gangers need supplies.
Step 7. Barter 25 option
Step 8. Repeat Step 6 again.
Step 9. Speech 25 option
Finally Repeat Steps 6 and 7 until you unlock the achievement/level up to level 30

Edit 1: You can also use this to sell 10,000 caps worth of goods since you get a Leather Armor everytime you succeed the Speech challenge.

Location: Red Rock Canyon
Requirement: Speech 33
Person: Jerry the Punk
Quest given: Cry Me A River

Go to Red Rock Canyon (I did it during the quest For the Republic, part 2 but I'm guessing you can probably do it anytime) and speak to Jerry the Punk. From the valley entrance he is located in the last of three tents up on the ridge just north of the training pit. He is the kid who is rambling poetry.
If you can't find him you could check out the Fallout: New Vegas wiki page about Jerry. http://fallout.wikia.com/wiki/Jerry_the_Punk
Go up to him and initiate dialogue.

The first time you talk to him ask what he is doing. Then follow these steps:

Step 1: Select 'What is this initiation?' and then 'That doesn't sound to bad.'
Step 2: Then you get a speech challenge [33 Speech].
Step 3: After that do NOT choose 'I could ask them for you.' (otherwise you get the quest Cry Me A River and that will break the dialogue cycle), instead take option 2 (Why don't you...) or 3 (Probably...).
Step 4: Then again do NOT say 'I could ask them for you.' - say: 'That's not really my problem, is it?'.
Step 5: Now you can start over from step 1. This seems so be a really fast way to get the achievement since you do not have to re-initiate dialogue between the challenges.


And no, it's not setup in five steps because of the NKOTB song :)
Please comment if it doesn't work. It did work for me when I tested it with the latest patch installed on Xbox 360.

Good luck!