IMPORTANT: don't just read the selected answer, all of the answers to this question provide good techniques to apply in different scenarios when it comes to conversations with NPCs. I chose the one which I think solve my own problem the best.

I tend to run mini sandbox adventures in which PCs are free to go around and interact with NPCs, locations, other PCs, etc. It seems to work for most of my players but one or two have complained that the whole process seems too meandering, especially that conversations with NPCs seem to take very long to resolve.

Before I ask how to make NPCs' conversations more succinct, I want to lay out some of my assumptions / resolutions:

• I like to make interesting NPCs so I tend to role play them out extensively. Major NPCs all have personalities, quirks and minor NPCs at least speak in character all the time


• I assume that I'll continue to play this mini-sandbox format for a while. Granted that changing the format might solve the problem but I will ask that as a separate question when the time comes


• I have already addressed some of the issues, which was that certain PCs tend to use a video-game approach and "exhaust" the NPC's dialogue on every possible topic. I told them to trust me as the GM that if I know what they're looking for, I'll weave it in and make it obvious in the narrative what they should do rather than present them with 100 doors and ask them to knock on all of them.


• I have also suspected that those players who had a problem didn't feel like they could contribute to the conversation and just sat there observing most of the time. My plan is to address this problem at its root (is this a character building problem, a player participation problem, etc.) but meanwhile, I am thinking of a rotation system during conversation.

With all of that said, what else can I do to make conversations with NPCs more succinct?

Handwave and summarise the boring stuff

I have struggled with a similar problem. I like to make my world immersive and give distinct characteristics to every NPC my group encounters. However it can lead to the players talking to an NPC for 10 minutes to purchase a meal.

As long as everyone is having fun this isn't a problem. However as you have pointed out some players can get bored of the extended dialogue. So what I tend to do is role play the first encounter with an NPC. Give the tavern keeper a personality when they first enter. Once the character is established however I won't play out the scene unless the players are trying to do something interesting with the conversation. Instead I simply state "you go a buy a meal from the bar, she charges you 3cp".

If the conversation is going to be mundane don't bother playing it out entirely. Keep your deep dialogue and extended scenes for the important stuff. This has the added bonus of reducing the number of distinct characters you need play/remember.

When the important information runs out

If a conversation starts out important and you want to play it at the table you can still use some similar techniques.

Mid-conversation should the PCs have gathered all the important information from the NPC simply tell them:

"You spend another 15 minutes talking to the sailor but learn nothing else interesting, except that he has a tattoo of a mermaid in a place he won't show you."

When talking to a powerful NPC, a Lord or ruler of some kind you can say things like:

"The King appears visibly frustrated by your continued questions, you recognise you only have one or two more before he tells you to leave"

If they don't take the hint to wrap it up, or this is too aggressive, remember that NPCs are people too and probably have other things to do.

"I'm afraid I have to go, never enough hours in the day for all the things I have to do"

Then have the NPC simply leave.

You also have the option to have another NPC interrupt them. If the NPC is a shop keeper they will have other customers, peasants will have children or friends, even the guard could show up to accuse them of loitering.

What about when the NPC has no reason end the conversation?

Sometimes you will find yourself in a situation where none of the above techniques will be logical. The hermit in the swamp who has nothing but time to talk to adventurers for example. In these situations you can take the opposite approach, bore the characters into ending it themselves.

PC: "How long have you been here?"

Hermit: "Well I first arrived on a moonswept night... the swamp was beautiful..."

DM: The Hermit launches into a 20 minute description of his arrival to the swamp.

PC: "But how long ago?"

Hermit: begins the same story...

With this approach you need to make the passage of time clear. The PCs are burning daylight talking to the NPC. This means they might not have time to get to that important MacGuffin tonight.

How to tell when to handwave

You mentioned in a comment on another answer this was something you were struggling with, I'll attempt to provide some advice.

From the GM side its pretty easy, if the party has gathered all the information you intend to give them then it's safe to handwave. Though you should be careful not to handwave away conversations that are entertaining and the entire table is invested in.

For example I had a very Australian NPC (I'm Australian too and I slipped with my accent when introducing the NPC) that the party thought was hilarious. His entire point was to give them directions to the important location in town. However I let the players continue talking to him until I ran out of Australian jokes at which point I had him leave to return to work.

The harder part is when you know there is still information to gather but the players have begun checking out of the conversation. It is hard to give advice for this as it will vary from group to group but some things to watch for are: players leaning back on their chair, players not joining in the conversation, phones or other distraction being looked at, and a reduction in the role playing effort.

At this point you can reduce the conversation to a dice roll. Have them role a social check and base the DC on how well the conversation has been going. On a success you give them all the important information in the handwaved summary. On a fail they may only get some or even none of it.

Summary

You want to use GM fiat and handwaving to indicate that the conversation continued but that they had all the important information. The players should trust that you have given them everything they could have gotten through continued conversation.

Have the NPCs break off the conversation when the point of diminishing returns has been reached.

This could be when you, as the GM, know that the most pertinent information has been delivered. Or, it could be when you notice that other players are become bored and disengaging.

Make only NPCs that are important interesting.

You could make other background NPCs just sort of melt into the background, thus signalling that they are not important.

Give the waiting characters something else to do.

This is a little harder to pull off, but if you give them something else to do and rotate the action to them for a few minutes, they will not be as bored, but will be left in suspense as the conversation continues, waiting their turn.

For example:

Super Interesting NPC: "Welcome Adventurers! Long have I waited..."

Bored PC: stares out the window, bored as hell, fingering their Battle Axe

GM: (After the dialogue continues for a bit) So, Bored PC, what are you doing while the Super Interesting NPC talks to So-and-So?

Bored PC: Guess I just stare out the window.

GM: "OK, after a few minutes, you see a stumbling-drunk dwarf come walking out of the Inn across the street. Shortly after, a pair of shady-looking humans exit the Inn and follow him down the dark alley..."

At this point, the Bored PC has some decisions to make and could even get some action in, if they want. The whole encounter could just be a quick couple of dice rolls, but it provides opportunity for them to become engaged in the game and might even trick them into interacting with an NPC!

Regarding the problem of delivering information...

Players can only absorb so much plot info before they are "full"

The plot that you have spent hours coming up with and going over in your mind is not going to be very clear to your players. They will need a painful amount of time to take it in and might never catch onto some of your plot elements.

If you feel that your players are bored, but there is more important information that they need, consider putting off that info until after next battle.

Give them some time to digest what they have discovered so far, then have the NPC show back up or even have another NPC deliver the required information.

I suggest that what you need is an "Early Out".

Essentially at most stages of conversation provide your players the opportunity to ask for more info or to explicitly finish the conversation.

You may also need to be more ruthless in deciding when the NPCs are talking too much in your scripts.

When you write the dialog, have a clear goal and a clear set of information the players need to know, and tell them very little else. Dress it up a little in purple prose and characterful tics, but don't go off on a historical tangent or suchlike unless you're confident the players are in the right mood and are of the right mindset to enjoy that.

As a DM, your first and foremost goal is to facilitate the players and arbitrate their actions, telling the story is their job.