diff --git a/src/Makefile.am b/src/Makefile.am
index c77a262617..1c2f770418 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -92,6 +92,7 @@ BITCOIN_CORE_H = \
   compressor.h \
   consensus/consensus.h \
   consensus/params.h \
+  consensus/validation.h \
   core_io.h \
   eccryptoverify.h \
   ecwrapper.h \
diff --git a/src/consensus/validation.h b/src/consensus/validation.h
new file mode 100644
index 0000000000..c92bec4fae
--- /dev/null
+++ b/src/consensus/validation.h
@@ -0,0 +1,80 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2014 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_CONSENSUS_VALIDATION_H
+#define BITCOIN_CONSENSUS_VALIDATION_H
+
+#include <string>
+
+/** "reject" message codes */
+static const unsigned char REJECT_MALFORMED = 0x01;
+static const unsigned char REJECT_INVALID = 0x10;
+static const unsigned char REJECT_OBSOLETE = 0x11;
+static const unsigned char REJECT_DUPLICATE = 0x12;
+static const unsigned char REJECT_NONSTANDARD = 0x40;
+static const unsigned char REJECT_DUST = 0x41;
+static const unsigned char REJECT_INSUFFICIENTFEE = 0x42;
+static const unsigned char REJECT_CHECKPOINT = 0x43;
+
+/** Capture information about block/transaction validation */
+class CValidationState {
+private:
+    enum mode_state {
+        MODE_VALID,   //! everything ok
+        MODE_INVALID, //! network rule violation (DoS value may be set)
+        MODE_ERROR,   //! run-time error
+    } mode;
+    int nDoS;
+    std::string strRejectReason;
+    unsigned char chRejectCode;
+    bool corruptionPossible;
+public:
+    CValidationState() : mode(MODE_VALID), nDoS(0), chRejectCode(0), corruptionPossible(false) {}
+    bool DoS(int level, bool ret = false,
+             unsigned char chRejectCodeIn=0, std::string strRejectReasonIn="",
+             bool corruptionIn=false) {
+        chRejectCode = chRejectCodeIn;
+        strRejectReason = strRejectReasonIn;
+        corruptionPossible = corruptionIn;
+        if (mode == MODE_ERROR)
+            return ret;
+        nDoS += level;
+        mode = MODE_INVALID;
+        return ret;
+    }
+    bool Invalid(bool ret = false,
+                 unsigned char _chRejectCode=0, std::string _strRejectReason="") {
+        return DoS(0, ret, _chRejectCode, _strRejectReason);
+    }
+    bool Error(std::string strRejectReasonIn="") {
+        if (mode == MODE_VALID)
+            strRejectReason = strRejectReasonIn;
+        mode = MODE_ERROR;
+        return false;
+    }
+    bool IsValid() const {
+        return mode == MODE_VALID;
+    }
+    bool IsInvalid() const {
+        return mode == MODE_INVALID;
+    }
+    bool IsError() const {
+        return mode == MODE_ERROR;
+    }
+    bool IsInvalid(int &nDoSOut) const {
+        if (IsInvalid()) {
+            nDoSOut = nDoS;
+            return true;
+        }
+        return false;
+    }
+    bool CorruptionPossible() const {
+        return corruptionPossible;
+    }
+    unsigned char GetRejectCode() const { return chRejectCode; }
+    std::string GetRejectReason() const { return strRejectReason; }
+};
+
+#endif // BITCOIN_CONSENSUS_VALIDATION_H
diff --git a/src/init.cpp b/src/init.cpp
index b8e095c12f..f4136f09e9 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -13,6 +13,7 @@
 #include "amount.h"
 #include "checkpoints.h"
 #include "compat/sanity.h"
+#include "consensus/validation.h"
 #include "key.h"
 #include "main.h"
 #include "miner.h"
diff --git a/src/main.cpp b/src/main.cpp
index c30f29f824..6b2e779db7 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -11,6 +11,7 @@
 #include "chainparams.h"
 #include "checkpoints.h"
 #include "checkqueue.h"
+#include "consensus/validation.h"
 #include "init.h"
 #include "merkleblock.h"
 #include "net.h"
@@ -1562,6 +1563,24 @@ bool UndoReadFromDisk(CBlockUndo& blockundo, const CDiskBlockPos& pos, const uin
     return true;
 }
 
+/** Abort with a message */
+bool AbortNode(const std::string& strMessage, const std::string& userMessage="")
+{
+    strMiscWarning = strMessage;
+    LogPrintf("*** %s\n", strMessage);
+    uiInterface.ThreadSafeMessageBox(
+        userMessage.empty() ? _("Error: A fatal internal error occured, see debug.log for details") : userMessage,
+        "", CClientUIInterface::MSG_ERROR);
+    StartShutdown();
+    return false;
+}
+
+bool AbortNode(CValidationState& state, const std::string& strMessage, const std::string& userMessage="")
+{
+    AbortNode(strMessage, userMessage);
+    return state.Error(strMessage);
+}
+
 } // anon namespace
 
 /**
@@ -1900,7 +1919,7 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin
             if (!FindUndoPos(state, pindex->nFile, pos, ::GetSerializeSize(blockundo, SER_DISK, CLIENT_VERSION) + 40))
                 return error("ConnectBlock(): FindUndoPos failed");
             if (!UndoWriteToDisk(blockundo, pos, pindex->pprev->GetBlockHash()))
-                return state.Abort("Failed to write undo data");
+                return AbortNode(state, "Failed to write undo data");
 
             // update nUndoPos in block index
             pindex->nUndoPos = pos.nPos;
@@ -1913,7 +1932,7 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin
 
     if (fTxIndex)
         if (!pblocktree->WriteTxIndex(vPos))
-            return state.Abort("Failed to write transaction index");
+            return AbortNode(state, "Failed to write transaction index");
 
     // add this block to the view's block chain
     view.SetBestBlock(pindex->GetBlockHash());
@@ -2008,7 +2027,7 @@ bool static FlushStateToDisk(CValidationState &state, FlushStateMode mode) {
                 setDirtyBlockIndex.erase(it++);
             }
             if (!pblocktree->WriteBatchSync(vFiles, nLastBlockFile, vBlocks)) {
-                return state.Abort("Files to write to block index database");
+                return AbortNode(state, "Files to write to block index database");
             }
         }
         // Finally remove any pruned files
@@ -2027,7 +2046,7 @@ bool static FlushStateToDisk(CValidationState &state, FlushStateMode mode) {
             return state.Error("out of disk space");
         // Flush the chainstate (which may refer to block index entries).
         if (!pcoinsTip->Flush())
-            return state.Abort("Failed to write to coin database");
+            return AbortNode(state, "Failed to write to coin database");
         nLastFlush = nNow;
     }
     if ((mode == FLUSH_STATE_ALWAYS || mode == FLUSH_STATE_PERIODIC) && nNow > nLastSetChain + (int64_t)DATABASE_WRITE_INTERVAL * 1000000) {
@@ -2036,7 +2055,7 @@ bool static FlushStateToDisk(CValidationState &state, FlushStateMode mode) {
         nLastSetChain = nNow;
     }
     } catch (const std::runtime_error& e) {
-        return state.Abort(std::string("System error while flushing: ") + e.what());
+        return AbortNode(state, std::string("System error while flushing: ") + e.what());
     }
     return true;
 }
@@ -2100,7 +2119,7 @@ bool static DisconnectTip(CValidationState &state) {
     // Read block from disk.
     CBlock block;
     if (!ReadBlockFromDisk(block, pindexDelete))
-        return state.Abort("Failed to read block");
+        return AbortNode(state, "Failed to read block");
     // Apply the block atomically to the chain state.
     int64_t nStart = GetTimeMicros();
     {
@@ -2151,7 +2170,7 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
     CBlock block;
     if (!pblock) {
         if (!ReadBlockFromDisk(block, pindexNew))
-            return state.Abort("Failed to read block");
+            return AbortNode(state, "Failed to read block");
         pblock = &block;
     }
     // Apply the block atomically to the chain state.
@@ -2858,11 +2877,11 @@ bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex** ppindex,
             return error("AcceptBlock(): FindBlockPos failed");
         if (dbp == NULL)
             if (!WriteBlockToDisk(block, blockPos))
-                return state.Abort("Failed to write block");
+                AbortNode(state, "Failed to write block");
         if (!ReceivedBlockTransactions(block, state, pindex, blockPos))
             return error("AcceptBlock(): ReceivedBlockTransactions failed");
     } catch (const std::runtime_error& e) {
-        return state.Abort(std::string("System error: ") + e.what());
+        return AbortNode(state, std::string("System error: ") + e.what());
     }
 
     if (fCheckForPruning)
@@ -2937,24 +2956,6 @@ bool TestBlockValidity(CValidationState &state, const CBlock& block, CBlockIndex
     return true;
 }
 
-
-
-
-
-
-
-
-bool AbortNode(const std::string &strMessage, const std::string &userMessage) {
-    strMiscWarning = strMessage;
-    LogPrintf("*** %s\n", strMessage);
-    uiInterface.ThreadSafeMessageBox(
-        userMessage.empty() ? _("Error: A fatal internal error occured, see debug.log for details") : userMessage,
-        "", CClientUIInterface::MSG_ERROR);
-    StartShutdown();
-    return false;
-}
-
-
 /**
  * BLOCK PRUNING CODE
  */
diff --git a/src/main.h b/src/main.h
index 6c380b104d..4bd339804e 100644
--- a/src/main.h
+++ b/src/main.h
@@ -89,16 +89,6 @@ static const unsigned int DATABASE_FLUSH_INTERVAL = 24 * 60 * 60;
 /** Maximum length of reject messages. */
 static const unsigned int MAX_REJECT_MESSAGE_LENGTH = 111;
 
-/** "reject" message codes */
-static const unsigned char REJECT_MALFORMED = 0x01;
-static const unsigned char REJECT_INVALID = 0x10;
-static const unsigned char REJECT_OBSOLETE = 0x11;
-static const unsigned char REJECT_DUPLICATE = 0x12;
-static const unsigned char REJECT_NONSTANDARD = 0x40;
-static const unsigned char REJECT_DUST = 0x41;
-static const unsigned char REJECT_INSUFFICIENTFEE = 0x42;
-static const unsigned char REJECT_CHECKPOINT = 0x43;
-
 struct BlockHasher
 {
     size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); }
@@ -230,8 +220,6 @@ void UnlinkPrunedFiles(std::set<int>& setFilesToPrune);
 
 /** Create a new block index entry for a given block hash */
 CBlockIndex * InsertBlockIndex(uint256 hash);
-/** Abort with a message */
-bool AbortNode(const std::string &msg, const std::string &userMessage="");
 /** Get statistics from node state */
 bool GetNodeStateStats(NodeId nodeid, CNodeStateStats &stats);
 /** Increase a node's misbehavior score. */
@@ -461,69 +449,6 @@ public:
      }
 };
 
-/** Capture information about block/transaction validation */
-class CValidationState {
-private:
-    enum mode_state {
-        MODE_VALID,   //! everything ok
-        MODE_INVALID, //! network rule violation (DoS value may be set)
-        MODE_ERROR,   //! run-time error
-    } mode;
-    int nDoS;
-    std::string strRejectReason;
-    unsigned char chRejectCode;
-    bool corruptionPossible;
-public:
-    CValidationState() : mode(MODE_VALID), nDoS(0), chRejectCode(0), corruptionPossible(false) {}
-    bool DoS(int level, bool ret = false,
-             unsigned char chRejectCodeIn=0, std::string strRejectReasonIn="",
-             bool corruptionIn=false) {
-        chRejectCode = chRejectCodeIn;
-        strRejectReason = strRejectReasonIn;
-        corruptionPossible = corruptionIn;
-        if (mode == MODE_ERROR)
-            return ret;
-        nDoS += level;
-        mode = MODE_INVALID;
-        return ret;
-    }
-    bool Invalid(bool ret = false,
-                 unsigned char _chRejectCode=0, std::string _strRejectReason="") {
-        return DoS(0, ret, _chRejectCode, _strRejectReason);
-    }
-    bool Error(std::string strRejectReasonIn="") {
-        if (mode == MODE_VALID)
-            strRejectReason = strRejectReasonIn;
-        mode = MODE_ERROR;
-        return false;
-    }
-    bool Abort(const std::string &msg) {
-        AbortNode(msg);
-        return Error(msg);
-    }
-    bool IsValid() const {
-        return mode == MODE_VALID;
-    }
-    bool IsInvalid() const {
-        return mode == MODE_INVALID;
-    }
-    bool IsError() const {
-        return mode == MODE_ERROR;
-    }
-    bool IsInvalid(int &nDoSOut) const {
-        if (IsInvalid()) {
-            nDoSOut = nDoS;
-            return true;
-        }
-        return false;
-    }
-    bool CorruptionPossible() const {
-        return corruptionPossible;
-    }
-    unsigned char GetRejectCode() const { return chRejectCode; }
-    std::string GetRejectReason() const { return strRejectReason; }
-};
-
 /** RAII wrapper for VerifyDB: Verify consistency of the block and coin databases */
 class CVerifyDB {
 public:
diff --git a/src/miner.cpp b/src/miner.cpp
index 804a688523..7a57b42e30 100644
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -8,6 +8,7 @@
 #include "amount.h"
 #include "chainparams.h"
 #include "consensus/consensus.h"
+#include "consensus/validation.h"
 #include "hash.h"
 #include "main.h"
 #include "net.h"
diff --git a/src/rpcblockchain.cpp b/src/rpcblockchain.cpp
index 4315c5ec18..79528db2fe 100644
--- a/src/rpcblockchain.cpp
+++ b/src/rpcblockchain.cpp
@@ -4,7 +4,9 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "checkpoints.h"
+#include "consensus/validation.h"
 #include "main.h"
+#include "primitives/transaction.h"
 #include "rpcserver.h"
 #include "sync.h"
 #include "util.h"
diff --git a/src/rpcmining.cpp b/src/rpcmining.cpp
index a6a8b9422f..d58d438573 100644
--- a/src/rpcmining.cpp
+++ b/src/rpcmining.cpp
@@ -6,6 +6,7 @@
 #include "amount.h"
 #include "chainparams.h"
 #include "consensus/consensus.h"
+#include "consensus/validation.h"
 #include "core_io.h"
 #include "init.h"
 #include "main.h"
diff --git a/src/rpcrawtransaction.cpp b/src/rpcrawtransaction.cpp
index e84d2693a2..3e37b797e8 100644
--- a/src/rpcrawtransaction.cpp
+++ b/src/rpcrawtransaction.cpp
@@ -4,13 +4,14 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "base58.h"
-#include "primitives/transaction.h"
+#include "consensus/validation.h"
 #include "core_io.h"
 #include "init.h"
 #include "keystore.h"
 #include "main.h"
 #include "merkleblock.h"
 #include "net.h"
+#include "primitives/transaction.h"
 #include "rpcserver.h"
 #include "script/script.h"
 #include "script/script_error.h"
diff --git a/src/test/checkblock_tests.cpp b/src/test/checkblock_tests.cpp
index 7abfad151e..51530c4de5 100644
--- a/src/test/checkblock_tests.cpp
+++ b/src/test/checkblock_tests.cpp
@@ -2,16 +2,11 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-//
-// Unit tests for block.CheckBlock()
-//
-
-
-
 #include "clientversion.h"
+#include "consensus/validation.h"
 #include "main.h"
-#include "utiltime.h"
 #include "test/test_bitcoin.h"
+#include "utiltime.h"
 
 #include <cstdio>
 
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index d7ea91607c..b6365b1b3a 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -2,6 +2,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include "consensus/validation.h"
 #include "main.h"
 #include "miner.h"
 #include "pubkey.h"
diff --git a/src/test/sighash_tests.cpp b/src/test/sighash_tests.cpp
index afb7a41bbd..87be2217c4 100644
--- a/src/test/sighash_tests.cpp
+++ b/src/test/sighash_tests.cpp
@@ -2,15 +2,16 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include "consensus/validation.h"
 #include "data/sighash.json.h"
 #include "main.h"
 #include "random.h"
-#include "serialize.h"
-#include "script/script.h"
 #include "script/interpreter.h"
+#include "script/script.h"
+#include "serialize.h"
+#include "test/test_bitcoin.h"
 #include "util.h"
 #include "version.h"
-#include "test/test_bitcoin.h"
 
 #include <iostream>
 
diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp
index 2a3083316e..d12535e438 100644
--- a/src/test/transaction_tests.cpp
+++ b/src/test/transaction_tests.cpp
@@ -7,12 +7,13 @@
 #include "test/test_bitcoin.h"
 
 #include "clientversion.h"
+#include "consensus/validation.h"
+#include "core_io.h"
 #include "key.h"
 #include "keystore.h"
 #include "main.h"
 #include "script/script.h"
 #include "script/script_error.h"
-#include "core_io.h"
 
 #include <map>
 #include <string>
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index 071fa9d52c..1c16e2092e 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -7,6 +7,7 @@
 
 #include "clientversion.h"
 #include "consensus/consensus.h"
+#include "consensus/validation.h"
 #include "main.h"
 #include "policy/fees.h"
 #include "streams.h"
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 3396a3a188..d892c66eda 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -9,6 +9,7 @@
 #include "checkpoints.h"
 #include "coincontrol.h"
 #include "consensus/consensus.h"
+#include "consensus/validation.h"
 #include "main.h"
 #include "net.h"
 #include "script/script.h"
diff --git a/src/wallet/walletdb.cpp b/src/wallet/walletdb.cpp
index 13eaf95aa6..f777926e72 100644
--- a/src/wallet/walletdb.cpp
+++ b/src/wallet/walletdb.cpp
@@ -6,6 +6,7 @@
 #include "wallet/walletdb.h"
 
 #include "base58.h"
+#include "consensus/validation.h"
 #include "main.h"
 #include "protocol.h"
 #include "serialize.h"