Central & Subsidiary Data Forts
Ice is installed *ON* a data fort.  Agenda, nodes, and upgrades are installed *IN* a data fort.  (Wendy Wallace, Netrunner-L, 5/1/96)
A subsidiary data fort goes away if (and as soon as) there are no cards left in or on it.  So even one piece of Ice will cause the data fort to stick around indefinitely. (Tom Wylie, Netrunner-L, 4/13/96)
Counters of any kind, including Virus counters, are not sufficient to maintain a subsidiary data fort. When the last card in or on the fort is removed, the fort collapses, period.  When that happens, the counters no longer exist.  (Wendy Wallace, Netrunner-L, 5/28/96)
The deck of cards and the player's hand are considered to be 'stored' in R&D and HQ respectively; they are not installed cards and are immune to effects that target installed cards.  (Netrunner FAQ v1.0, 5/23/96)
Central data forts (HQ, R&D, and the Archives) always exist, even if there are no cards in them.  (Netrunner Rulebook, pp9-10; Sparky, Netrunner-L, 5/30/96)

Ice & Icebreakers
When the Runner passes a piece of Ice, the Ice remains in play; it must be passed every time the Runner runs on the fort.  (Netrunner FAQ v1.0, 5/23/96)
When Ice is trashed, any Ice that is outside of it moves in to fill the vacuum left by its predecessor.  (Sparky, Netrunner-L, 4/19/96)
An Icebreaker that targets any of the Ice's keywords will work on that piece of Ice.  (Wendy Wallace, Netrunner-L, 4/29/96)
If a piece of rezzed Ice is modified by some external effect, then derezzed, it will "remember" the modification if rezzed again.  (Wendy Wallace, Netrunner-L, 4/30/96)  If it is uninstalled, however, the modifications are "forgotten."  (Sparky, Netrunner-L, 11/11/96)
The Runner can break the subroutines on a piece of Ice in any order.  When the Runner has completed this process, the unbroken subroutines take effect in the order they are printed on the card.  (Wendy Wallace, Netrunner-L, 4/30/96)
The strength of Ice and Icebreakers can be negative. (Glenn Elliott, Netrunner-L, 5/9/96)
In general, you can only use an Icebreaker's abilities during an encounter with a piece of Ice, and that piece of Ice must correspond to the type of subroutine that the Icebreaker can break.  Any exceptions to this are noted in the individual Icebreaker's card text.  (Skipper Pickle, Netrunner-L, 1/12/98)
Any effect that duplicates the subroutines on a piece of Ice only duplicates subroutines generated by the text on the card.  (Sparky, Netrunner-L, 11/18/96; Tom Wylie, 8/26/97)
Use the following procedure to compute the strength of a piece of ice when multiple effects can change it:
 1)(Approach) Corp: Apply any text written on the piece of ice which modifies its strength.
  2) Corp: Apply any other special effect which changes the strength of the ice. As always when multiple effects apply at the same time you choose the order of those effects.
  3)(Encounter) Runner: Apply effects which modify the strength of the encountered piece of ice.
  4) Runner: When you want to break any subroutines on this piece of ice increase the strength of your icebreaker if necessary. (Sensei, 11-03-2000)

Tracing
The corp can successfully trace with an investment of zero bits.  After all, if trace and link are equal, the trace is successful.  If you don't have a link card out, you're stuck at a link of zero.  (Sparky, Netrunner-L, 4/24/96)
You may only use one Base Link card per trace attempt.  You cannot use parts of two.  You can use as many other non-Base Link cards to increase your link as you like.
(Sparky, Netrunner-L, 5/30/96)
Both players have a right to know the number of bits in the other player's bit pool at any time (see "Public Knowledge").  (Skipper Pickle, Netrunner-L, 1/8/98)
You can use a Hidden Resource to pay for a trace.  You don't have to reveal the Hidden Resource until each player has revealed the amount he or she is spending.  Thus, you might actually note an amount greater than the amount in your bit pool.  (Skipper Pickle, Netrunner-L, 1/8/98)

Taking Actions and Playing Cards
You cannot combine actions by playing a card that says make a run and gain some benefit at the same time that you use an installed card's special effect to gain a different benefit.  (Wendy Wallace, Netrunner-L, 4/26/96)
If a card tells you to make a run (or do anything else that normally requires an action), anything the card tells you to do is included in action of playing the card; you do not have to take an additional action to make that run, unless the card specifies otherwise.  (Wendy Wallace, Netrunner-L, 4/30/96)
Preps and Operations are assumed to be trashed before their effects occur.  This is the order 1) pay for the card and make all decisions; 2) put the card in the Trash/Archives; 3) execute the card instructions. (Sparky, Netrunner-L, 8/27/96)

Stealth and Noise
You do not have to have Stealth cards in play in order to use Noisy cards.  (Wendy Wallace, Netrunner-L, 4/26/96)

Card Effects
Either player can use special effects during the same times the Corp can rez cards.  However, if the effect requires a cost of one or more actions, it can only be used during that player's turn.  (Netrunner FAQ v1.0, 5/23/96)
If the Corp and the Runner can both perform functions (the Corp rezzing a card, or the Runner using a card effect, for example) at the same time, the Runner always gets the first opportunity to perform any functions he or she likes, and then the Corp performs any of its functions. (Sparky, Netrunner-L, 10/11/96)
If a player has multiple effects to process at any given time (e.g., start of turn, end of turn, start of run, end of run), that player chooses the order in which the effects are processed.  Thus the Corp could rez a Holovid Campaign at the start of his or her turn, then gain a bit from that Holovid Campaign at the start of that turn.  (Sparky, Netrunner-L, 5/22/96)
When card effect A prohibits an effect of type B, the blanket prohibition always takes precedence, and effect B does not happen (even if a card "forces" you to do it).  (Sparky, Netrunner-L, 7/10/96)
If an effect targets multiple cards, all decisions are made regarding those targets before the effect is resolved (e.g., if the Runner plays Hunt Club BBS, all of the cards to be exposed are chosen before they are exposed) (Netrunner FAQ v1.0, 5/23/96)
If an effect generates multiple consequences, those consequences are processed in the order they appear on the card.  (JD Wiker, Netrunner-L, 2/11/96)

Trashing Cards
Only cards with a trash cost (nodes and upgrades) can be usually be trashed.  These are the cards with the trashcan in the lower right corner.  If you pay that number of bits, you can trash the card instead of watching it go right back to where you got it.  (Sparky,    Netrunner-L, 4/18/96)
If a player's effect trashes a one or more of a particular card type, that player chooses which specific cards are trashed, unless the effect indicates otherwise.  For example, if an Ice subroutine trashes a program, the Corp chooses which program is trashed.  (Wendy Wallace, Netrunner-L, 4/26/96)  That player also chooses the order in which the cards are trashed.  (Sparky, Netrunner-L, 5/15/96)  In the case of an effect that trashes multiple cards, all of the cards are trashed (resolving the trashing effect), then the consequences of the trashing are dealt with.  (Netrunner FAQ v1.0, 5/23/96)
When the Runner accesses a card, that card's effect, if any, takes effect before the Runner has an opportunity to trash it.  (Sparky, Netrunner-L, 5/19/96)  When the Runner trashes cards in a fort, all of the trashing happens simultaneously; there is no "sequence" to the trashing that occurs at the end of a run.  (Sparky, Netrunner-L, 7/10/96)
If the Runner is tagged, the Corp may trash a Hidden Resource in the same way that it can trash any other  resource.  (Sparky, Netrunner-L, 10/18/96)
If the Runner manages to trash an installed agenda with advancement counters on it, those advancement counters are lost.  (JD Wiker, Netrunner-L, 12/23/96)

Archives/Trash
Anytime a Corp card that the Runner has seen goes to the Archives it goes to the face-up stack.  (Wendy Wallace, Netrunner-L, 5/1/96)  Any card that goes to the Archives that has not been seen by the Runner goes to the face-down pile.  (JD Wiker, Netrunner-L, 1/20/96)
No rearrangement of the Trash or Archives is allowed, except as specified by the rules or a card effect. (Sparky!, Netrunner-L, 5/8/96)
The Corp may look through the Runner's trash at any time; the Runner may look through the face-up cards in the Corp's Archives at any time.  When players recover a card from respective discard piles, it is common courtesy to show the opponent which card they are retrieving.  (Sparky, Netrunner-L, 7/25/96)

Dealing & Taking Damage
Each subroutine is a separate source of damage.  For instance, if three subroutines on a single piece of Ice do 1 brain damage each, the Runner must take or prevent each 1 separately, rather than taking (or preventing) 3 brain damage all at once.  (Sparky!, Netrunner-L, 5/14/96)
Each source of damage must be dealt with separately and immediately.  Let's say you're using Blink to break through Cortical Scrub.  You roll a 3 attempting to break the "Do 1 brain damage" subroutine.  You must immediately deal with the 3 Net damage from Blink. Assuming you survive, you then attempt to break the "End the run" subroutine.  You roll a 1; you take 1 Net damage from Blink.  Now you take the consequences of the unbroken subroutines 1 brain damage and an ended run. (Sparky!, Netrunner-L, 5/14/96)
Cards that go to the trash as the result of damage are chosen randomly, and they go to the trash in the order in which they were randomly chosen.  (Sparky, Netrunner-L, 5/15/96)

Discarding
You only check your hand size at the end of your turn.  If your hand size is reduced, you are not forced to automatically discard.  (Sparky, Netrunner-L, 8/8/96)
You only discard down to your maximum hand size at the end of your turn.  If your hand size becomes less than zero, but you still have cards in your hand, you have until the end of your turn to get your hand size up to zero, or you will flatline at the end of the turn.  (Sparky, Netrunner-L, 5/22/96)
You cannot end your turn with more cards than allowed by your maximum hand size.  Although the automatic draw at the start of the Corp's turn is a start-of-turn effect, discarding isn't an end-of-turn effect, so it doesn't fit into timing.  It's just the last thing you do during your turn.  Check for a discard after all 'end of turn' effects.  (Sparky, Netrunner-L, 7/25/96)
Hand size can be negative, but when it is negative, it is treated as 0 for all purposes except raising them back up again. So if a Corp gets really slammed with Gremlins, it has to do a lot of work (or forgo actions) to get its hand size above 0 again, but it doesn’t lose. (Tom Wylie 11/12/99). The same applies to the Runner though he has to survive flatlining at the end of his turn because he has to discard more cards than he can. (Sensei, 11-03-2000)

Viruses & Forgoing Actions
Virus counters are given only after a successful run is completed.  (Sparky, Netrunner-L, 9/9/96)
As soon as the Corp declares three actions forgone, all Virus counters given to the Corp are removed.  (Charles Keith-Stanley, Netrunner-L, 5/3/96)
The Corp's mandatory draw is NOT an action.  The Corp still draws a card at the beginning of each Corp turn, even if the Corp has foregone all of the actions for that turn.
(Wendy Wallace, Netrunner-L, 5/23/96)
Virus counters remain in play even if the program that gave them is uninstalled.  (Sparky, Netrunner-L, 5/22/96)
You can remove virus counters (and be forced to forgo your next three actions) any time you can rez a card. (Sparky, Netrunner-L, 7/17/96)
Forgoing actions to remove virus counters is cumulative if you forgo your next three actions to remove viruses, and forgo another three before you've paid the penalty for the first removal, you will forgo six consecutive actions.  (Sparky, Netrunner-L, 9/3/96)
If the player is forced to forgo actions, actions dedicated to a specific purpose (e.g., Wilson, Weeflerunner Apprentice) can be used to fulfill the penalty. (Sparky, Netrunner-L, 9/12/96)

Cumulative Effects
Unless the card text indicates otherwise, a card referring to itself (e.g., Broker) refers only to that specific card, not to the other versions of that card that are also in play.  (Sparky!, Netrunner-L, 5/6/96)

Gaining Actions
You can only take actions during your own turn.  (Sparky!, Netrunner-L, 5/7/96)  Neither player can use effects to gain actions during the other player's turn.  (Netrunner
FAQ v1.0, 5/23/96)
When an effect gives you an extra action, you gain that action immediately, even if you gained the action as a result of rezzing something after the last action of your turn.  (Sparky!, Netrunner-L, 5/9/96)
When a card states that you will get an extra action per turn, you must declare when you use it.  If the card is trashed during the Corp's turn and the Corp has not declared that it had used the extra action, the extra action is lost.  (Sparky, Netrunner-L, 7/26/96)
You must use all of your actions, if possible.  You may not gain an action that you can neither use nor forgo, unless a card's text says otherwise.  (Skipper Pickle, Netrunner-L, 10/14/98)

Paying Costs
You cannot spend resources you don't have.  If you have 0 agenda points, and you are required to spend 1 or more agenda points to activate an effect, you cannot activate
the effect; another good example of this is South African Mining Corp, which requires you to spend 3 actions to gain 6 bits  if you don't have 3 actions immediately available to you, you can't gain the 6 bits. (Sparky!, Netrunner-L, 5/8/96)

Accessing Cards
Unless a node specifically says otherwise, if it is installed, it must be rezzed in order to take effect. Of all the nodes and upgrades in v1.0 and Proteus, only Virus Test Site has any effect when the Runner accesses it while it is both installed AND unrezzed (it does 1--and only 1--Net damage to the Runner, regardless of the number of advancement counters on it).  (Sparky!, Netrunner-L, 5/13/96)
The Runner chooses the order in which he or she will access cards, including any draws or face-down cards as well. That's the order in which they affect the Runner.  If the Runner survives accessing all the cards there, the Runner can then score agenda and pay to trash nodes and upgrades.  (Sparky, Netrunner-L, 6/12/96)  The effect of each accessed card must be dealt with separately and immediately, before accessing the next card.  (Sparky, Netrunner-L, 11/18/96)
If you are accessing multiple cards from HQ, you can choose the order in which you take picks, and intermingle them with accessing upgrades as you wish.  (Sparky, Netrunner-L, 11/18/96)
If you are accessing multiple cards from R&D, you can choose the order in which you take draws from the top of R&D, and intermingle them with accessing upgrades as you
wish; you cannot alter the order in which you draw cards from the top of R&D.  (Sparky, Netrunner-L, 11/18/96)
If you are accessing cards from the Archives, you take all the cards in the face-down pile and put them in the face-up pile, then access them one at a time, working down the pile.  You can intermingle accessing cards in the Archives with with accessing upgrades as you wish. (Sparky, Netrunner-L, 11/18/96)
When the Runner accesses cards stored in HQ, the Corp always has the right to know which cards were accessed. (Skipper Pickle, Netrunner-L, 11/11/97)

Advancing Cards & Scoring Agenda
An agenda must be installed before it can be scored, even if it has an effective difficulty of 0.  (Sparky, Netrunner-L, 5/19/96)
It is legal to advance an agenda beyond its difficulty. (Sparky, Netrunner-L, 6/12/96)
"Advancing a card" is spending an action and a bit to add an advancement counter to one of your installed cards that can be advanced.  "Advancing a card" is simply one of several methods of adding an advancement counters to a card.  (Sparky, Netrunner-L, 6/12/96)
Unless a card effect prevents it, the Runner must score any agenda accessed; if an additional cost must be paid and the Runner does not pay it, the agenda is not scored and
returns to the fort from which it was accessed. (Sparky, Netrunner-L, 10/2/96)

Installing Programs
Once a program is installed in one location, you cannot voluntarily move it around to another location (e.g., a program installed in regular MU cannot be moved to a Daemon without removing the program from play first). (Netrunner FAQ v1.0, 5/23/96)
MU will never prohibit you from installing a program, but sometimes you'll have to trash something else in play to do so.  (Sparky, Netrunner-L, 6/17/96)

Prevention Effects
A prevention effect essentially occurs "before" the effect it is preventing.  (Sparky, Netrunner-L, 6/17/96)
You can't use prevention effects unless you have something to prevent (e.g., Emergency Self-Construct can only be triggered when you flatline)  (Sparky, Netrunner-L, 7/10/96)  Any prevention effect on a card is also a condition of play for that card. (Sparky, Netrunner-L, 12/2/96)
If you prevent a cost from being paid, you prevent that cost's effect from being played.  So, for instance, if you activate a Lockjaw by trashing it, but use Umbrella Policy to prevent the Lockjaw from being trashed, your Lockjaw will be saved and your Umbrella Policy will be gone, but you will not be able to give any icebreaker a benefit of +2 strength.  (Skipper Pickle,Netrunner-L, 9/29/98)

Making Runs and Jacking Out
Unless a card effect says otherwise, there is no opportunity for the Runner to jack out between the start of a run and the encounter with the first piece of Ice. (Sparky, Netrunner-L, 7/22/96)

Voluntary Effects
You cannot reveal one of your own cards just because you want to do so.  You must have a reason--a card or game effect--to reveal it.  (Sparky, Netrunner-L, 9/11/96)
You cannot voluntarily trash, or otherwise uninstall, an installed card unless a game effect specifically allows you to do so.  (Skipper Pickle, Netrunner-L, 11/4/97)

Public Knowledge
Players have a right to know following information about their opponents at any time  the number of bits in the opponent's bit pool, the number of cards in the opponent's hand, the number of cards remaining in the opponent's draw pile, the number of cards in the opponent's discard pile, the number of tokens/counters on any card that implements tokens/counters.  (Skipper Pickle, Netrunner-L, 9/18/98)
The Runner knows the following about face-down cards in a subsidiary data fort  how many cards are in the fort, how many advancement counters are on each card, and what order the cards went into the fort; thus, if the Runner played Hunt Club BBS, the Corp would not be allowed to shuffle cards around inside a single data fort.  This prevents having advancement counters end up on a card that didn't previously have them, which would be "unsportsmanlike conduct."  (Skipper Pickle, Netrunner-L, 9/10/98)