Fallout 4 - The "Good" Ending

So, you've been playing through Fallout 4 and seen that you can side with a particular faction and can have different outcomes to the main base game depending on which one that you have pledged your allegiance to.  There is though a fifth ending, one where all of the factions are happy with (or at the very least tolerate) each other, with the exception of the Institute, 'cause nobody like those guys!  If you want to get to this state of dysfunctional utopia within a crumbling Boston, then the following steps will prove very handy...

(It goes without saying, that there are spoilers for the game in the steps below.  If you haven't played the game, or don't want to know what happens in it yet, what are you doing here?  For an overview of all of the quests that are available in the game, check out the Fallout 4 Wiki Quests Page.)

Step 1:

Before you complete the mission "Reunions", complete all of the main and side quests (just one time for each of the repeatable side quests) for the Brotherhood of Steel recon team.  Talk Brandis down from being crazy.

Step 2:

Complete the mission "Reunions" and "Dangerous Minds" (and to get the best completion, keep Preston at the Castle).

Step 3:

  • You will have received "Tradecraft" and "Shadow of Steel"DO NOT advance in either of these two quests.
  • Focus on the Minutemen as you progress through the main quest line.  Use the Minutemen to gain access to the Institute.
  • Get yourself banished from the Institute.  You can have a nosey around for a bit in there and poke and prod at things, but if you do you'll have to whack someone to get banished.  You may safely complete "Institutionalized", but do not progress any farther before getting yourself kicked out.  Don't even talk speak to Father again after completing "Institutionalized"DO NOT complete the mission "Synth Retention" (give the holotape to Sturges).

Step 4:

  • You will have received "Form Ranks" for the Minutemen.  DO NOT advance this quest.
  • DO NOT start "Defend the Castle".  Don't even go to the Castle.  You know what, for now, forget the Castle even exists!
  • Complete all quests for the Brotherhood from "Shadow of Steel" to "Show No Mercy"DO NOT complete "Show No Mercy", don't even get on the vertibird, decide that you are like Mr. T and that "I ain't flying in no vertibird fool!".  Grab ALL of the sidequests from the Brotherhood and keep them open.

Step 5:

Complete "Form Ranks" and "Defend the Castle".  Start the mission "The Nuclear Option" for the Minutemen, but DO NOT complete it.

Step 6:

Complete all the Railroad quests from "Tradecraft" to "Randolph Safehouse 6".

Step 7:

Complete "The Nuclear Option"

And there you have it!  If you've followed this lot so far then all of the factions will be loving you.  Many of the factions quests and side quests are repeatable, and the Railroad has a whole new line of quests for you, so go wild in your (relatively) peacful Commonwealth, but don't talk to P.A.M. who after this is a bit peeved and wants to start a war with the Brotherhood!