diff --git a/_includes/guide_intro.md b/_includes/guide_intro.md
index 90663ee4..cd99ac8d 100644
--- a/_includes/guide_intro.md
+++ b/_includes/guide_intro.md
@@ -6,7 +6,8 @@ http://opensource.org/licenses/MIT.
{% autocrossref %}
The Developer Guide aims to provide the information you need to understand
-Bitcoin and start building Bitcoin-based applications. To make the best use of
+Bitcoin and start building Bitcoin-based applications, but it is [not a
+specification][]. To make the best use of
this documentation, you may want to install the current version of Bitcoin
Core, either from [source][core git] or from a [pre-compiled executable][core executable].
diff --git a/_includes/guide_p2p_network.md b/_includes/guide_p2p_network.md
index 62f04841..c4a0a801 100644
--- a/_includes/guide_p2p_network.md
+++ b/_includes/guide_p2p_network.md
@@ -226,6 +226,7 @@ These messages are aggressively broadcast using the `alert` message, being sent
These messages are signed by a specific ECDSA private key that only a small number of developers control.
-**Resource:** More details about the structure of messages and a complete list of message types can be found at the [Protocol Specification](https://en.bitcoin.it/wiki/Protocol_specification) page of the Bitcoin Wiki.
+**Resource:** More details about the structure of messages and a complete list of message types can be found in
+the [P2P reference section][section P2P reference].
{% endautocrossref %}
diff --git a/_includes/ref_intro.md b/_includes/ref_intro.md
index 150a1195..16cbc8ae 100644
--- a/_includes/ref_intro.md
+++ b/_includes/ref_intro.md
@@ -5,8 +5,9 @@ http://opensource.org/licenses/MIT.
{% autocrossref %}
-The Developer Reference aims to provide specifications and API information
-to help you start building Bitcoin-based applications. To make the best use of
+The Developer Reference aims to provide technical details and API information
+to help you start building Bitcoin-based applications, but it is [not a
+specification][]. To make the best use of
this documentation, you may want to install the current version of Bitcoin
Core, either from [source][core git] or from a [pre-compiled executable][core executable].
@@ -23,3 +24,43 @@ links will be shown in blue. If you hover over a cross-reference link, a brief
definition of the term will be displayed in a tooltip.
{% endautocrossref %}
+
+#### Not A Specification
+{:.no_toc}
+
+{% autocrossref %}
+
+The Bitcoin.org Developer Documentation describes how Bitcoin works to
+help educate new Bitcoin developers, but it is not a specification---and
+it never will be.
+
+Bitcoin security depends on consensus. Should your program diverge from
+consensus, its security is weakened or destroyed. The cause of the
+divergence doesn't matter: it could be a bug in your program, it could
+be an [error in this documentation][errors in docs] which you
+implemented as described, or it could be you do everything right but the
+majority software on the network [behaves unexpectedly][v0.8 chain
+fork]. The specific cause will not matter to the users of your software
+whose wealth is lost.
+
+The only correct specification of consensus behavior is the actual
+program behavior of the majority software on the network. As that
+behavior is subject to arbitrary inputs in a large variety
+of unique environments, it cannot ever be fully documented here or
+anywhere else.
+
+However, the Bitcoin Core developers are working on making their
+consensus code portable so other implementations can use it. Bitcoin
+Core 0.10 will provide `libbitcoinconsensus`, a first attempt at
+exporting some consensus code. Future versions of Bitcoin Core will
+likely provide consensus code that is more complete, more portable, and
+more consistent in diverse environments.
+
+In addition, we also warn you that this documentation has not been
+extensively reviewed by Bitcoin experts and so likely contains numerous
+errors. At the bottom of the menu on the left, you will find links that
+allow you to report an issue or to edit the documentation on GitHub.
+Please use those links if you find any errors or important missing
+information.
+
+{% endautocrossref %}
diff --git a/_includes/ref_p2p_networking.md b/_includes/ref_p2p_networking.md
index 27c688b9..88d99aee 100644
--- a/_includes/ref_p2p_networking.md
+++ b/_includes/ref_p2p_networking.md
@@ -9,8 +9,8 @@ http://opensource.org/licenses/MIT.
{% autocrossref %}
-This section describes the Bitcoin P2P network protocol (but it is not a
-specification). It does not describe the discontinued direct [IP-to-IP
+This section describes the Bitcoin P2P network protocol (but it is [not a
+specification][]). It does not describe the discontinued direct [IP-to-IP
payment protocol][], the [BIP70 payment protocol][payment protocol], the
[GetBlockTemplate mining protocol][section getblocktemplate], or any
network protocol never implemented in an official version of Bitcoin Core.
diff --git a/_includes/references.md b/_includes/references.md
index 47e2f9d5..b16dbc3e 100644
--- a/_includes/references.md
+++ b/_includes/references.md
@@ -300,6 +300,7 @@ http://opensource.org/licenses/MIT.
[locktime parsing rules]: /en/developer-guide#locktime_parsing_rules
[Merge Avoidance subsection]: /en/developer-guide#merge-avoidance
[micropayment channel]: /en/developer-guide#term-micropayment-channel
+[not a specification]: /en/developer-reference#not-a-specification
[raw transaction format]: /en/developer-reference#raw-transaction-format
[RPC]: /en/developer-reference#remote-procedure-calls-rpcs
[RPCs]: /en/developer-reference#remote-procedure-calls-rpcs
@@ -309,12 +310,14 @@ http://opensource.org/licenses/MIT.
[section hash byte order]: /en/developer-reference#hash-byte-order
[section merkle trees]: /en/developer-reference#merkle-trees
[section merkleblock example]: /en/developer-examples#parsing-a-merkleblock
+[section p2p reference]: /en/developer-reference#p2p-network
[section protocol versions]: /en/developer-reference#protocol-versions
[section serialized blocks]: /en/developer-reference#serialized-blocks
[section simple raw transaction]: /en/developer-examples#simple-raw-transaction
[section verifying payment]: /en/developer-guide#verifying-payment
[signature script modification warning]: /en/developer-reference#signature_script_modification_warning
[transaction object format]: /en/developer-reference#term-transaction-object-format
+[v0.8 chain fork]: /en/alert/2013-03-11-chain-fork
[Verification subsection]: /en/developer-guide#verifying-payment
[X509Certificates]: /en/developer-examples#term-x509certificates
@@ -371,6 +374,7 @@ http://opensource.org/licenses/MIT.
[ECDSA]: https://en.wikipedia.org/wiki/Elliptic_Curve_DSA
[Electrum server]: https://github.com/spesmilo/electrum-server
[Eloipool]: https://gitorious.org/bitcoin/eloipool
+[errors in docs]: https://github.com/bitcoin/bitcoin.org/issues?q=is%3Aissue+label%3A%22Dev+Docs%22
[forum tech support]: https://bitcointalk.org/index.php?board=4.0
[high-speed block relay network]: https://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg03189.html
[HMAC-SHA512]: https://en.wikipedia.org/wiki/HMAC
diff --git a/en/developer-documentation.md b/en/developer-documentation.md
index ee0c5697..7ea5c3cf 100644
--- a/en/developer-documentation.md
+++ b/en/developer-documentation.md
@@ -14,7 +14,7 @@ title: "Developer Documentation - Bitcoin"
diff --git a/en/developer-reference.md b/en/developer-reference.md
index 148d0dea..2c4ff247 100644
--- a/en/developer-reference.md
+++ b/en/developer-reference.md
@@ -10,7 +10,7 @@ title: "Developer Reference - Bitcoin"
# Bitcoin Developer Reference
-Find technical specifications and API documentation.
+Find technical details and API documentation.
Developer Guide(How Bitcoin works)
-
Developer Reference(Specifications and APIs)
+
Developer Examples(Examples you can use)