diff --git a/src/wallet.cpp b/src/wallet.cpp
index 3c3d890e2e..6601575d88 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -33,6 +33,7 @@ struct CompareValueOnly
 
 CPubKey CWallet::GenerateNewKey()
 {
+    AssertLockHeld(cs_wallet); // mapKeyMetadata
     bool fCompressed = CanSupportFeature(FEATURE_COMPRPUBKEY); // default to compressed public keys if we want 0.6.0 wallets
 
     RandAddSeedPerfmon();
@@ -58,6 +59,7 @@ CPubKey CWallet::GenerateNewKey()
 
 bool CWallet::AddKeyPubKey(const CKey& secret, const CPubKey &pubkey)
 {
+    AssertLockHeld(cs_wallet); // mapKeyMetadata
     if (!CCryptoKeyStore::AddKeyPubKey(secret, pubkey))
         return false;
     if (!fFileBacked)
@@ -93,6 +95,7 @@ bool CWallet::AddCryptedKey(const CPubKey &vchPubKey,
 
 bool CWallet::LoadKeyMetadata(const CPubKey &pubkey, const CKeyMetadata &meta)
 {
+    AssertLockHeld(cs_wallet); // mapKeyMetadata
     if (meta.nCreateTime && (!nTimeFirstKey || meta.nCreateTime < nTimeFirstKey))
         nTimeFirstKey = meta.nCreateTime;
 
@@ -200,6 +203,7 @@ public:
 
 bool CWallet::SetMinVersion(enum WalletFeature nVersion, CWalletDB* pwalletdbIn, bool fExplicit)
 {
+    AssertLockHeld(cs_wallet); // nWalletVersion
     if (nWalletVersion >= nVersion)
         return true;
 
@@ -233,6 +237,7 @@ bool CWallet::SetMinVersion(enum WalletFeature nVersion, CWalletDB* pwalletdbIn,
 
 bool CWallet::SetMaxVersion(int nVersion)
 {
+    AssertLockHeld(cs_wallet); // nWalletVersion, nWalletMaxVersion
     // cannot downgrade below current version
     if (nWalletVersion > nVersion)
         return false;
@@ -325,6 +330,7 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
 
 int64_t CWallet::IncOrderPosNext(CWalletDB *pwalletdb)
 {
+    AssertLockHeld(cs_wallet); // nOrderPosNext
     int64_t nRet = nOrderPosNext++;
     if (pwalletdb) {
         pwalletdb->WriteOrderPosNext(nOrderPosNext);
@@ -336,6 +342,7 @@ int64_t CWallet::IncOrderPosNext(CWalletDB *pwalletdb)
 
 CWallet::TxItems CWallet::OrderedTxItems(std::list<CAccountingEntry>& acentries, std::string strAccount)
 {
+    AssertLockHeld(cs_wallet); // mapWallet
     CWalletDB walletdb(strWalletFile);
 
     // First: get all CWalletTx and CAccountingEntry into a sorted-by-order multimap.
@@ -1482,6 +1489,7 @@ string CWallet::SendMoneyToDestination(const CTxDestination& address, int64_t nV
 
 DBErrors CWallet::LoadWallet(bool& fFirstRunRet)
 {
+    AssertLockHeld(cs_wallet); // setKeyPool
     if (!fFileBacked)
         return DB_LOAD_OK;
     fFirstRunRet = false;
@@ -1507,6 +1515,7 @@ DBErrors CWallet::LoadWallet(bool& fFirstRunRet)
 
 bool CWallet::SetAddressBook(const CTxDestination& address, const string& strName, const string& strPurpose)
 {
+    AssertLockHeld(cs_wallet); // mapAddressBook
     std::map<CTxDestination, CAddressBookData>::iterator mi = mapAddressBook.find(address);
     mapAddressBook[address].name = strName;
     if (!strPurpose.empty()) /* update purpose only if requested */
@@ -1523,6 +1532,7 @@ bool CWallet::SetAddressBook(const CTxDestination& address, const string& strNam
 
 bool CWallet::DelAddressBook(const CTxDestination& address)
 {
+    AssertLockHeld(cs_wallet); // mapAddressBook
     mapAddressBook.erase(address);
     NotifyAddressBookChanged(this, address, "", ::IsMine(*this, address), "", CT_DELETED);
     if (!fFileBacked)
@@ -1736,6 +1746,7 @@ std::map<CTxDestination, int64_t> CWallet::GetAddressBalances()
 
 set< set<CTxDestination> > CWallet::GetAddressGroupings()
 {
+    AssertLockHeld(cs_wallet); // mapWallet
     set< set<CTxDestination> > groupings;
     set<CTxDestination> grouping;
 
@@ -1828,6 +1839,7 @@ set< set<CTxDestination> > CWallet::GetAddressGroupings()
 
 set<CTxDestination> CWallet::GetAccountAddresses(string strAccount) const
 {
+    AssertLockHeld(cs_wallet); // mapWallet
     set<CTxDestination> result;
     BOOST_FOREACH(const PAIRTYPE(CTxDestination, CAddressBookData)& item, mapAddressBook)
     {
@@ -1909,21 +1921,25 @@ void CWallet::UpdatedTransaction(const uint256 &hashTx)
 
 void CWallet::LockCoin(COutPoint& output)
 {
+    AssertLockHeld(cs_wallet); // setLockedCoins
     setLockedCoins.insert(output);
 }
 
 void CWallet::UnlockCoin(COutPoint& output)
 {
+    AssertLockHeld(cs_wallet); // setLockedCoins
     setLockedCoins.erase(output);
 }
 
 void CWallet::UnlockAllCoins()
 {
+    AssertLockHeld(cs_wallet); // setLockedCoins
     setLockedCoins.clear();
 }
 
 bool CWallet::IsLockedCoin(uint256 hash, unsigned int n) const
 {
+    AssertLockHeld(cs_wallet); // setLockedCoins
     COutPoint outpt(hash, n);
 
     return (setLockedCoins.count(outpt) > 0);
@@ -1931,6 +1947,7 @@ bool CWallet::IsLockedCoin(uint256 hash, unsigned int n) const
 
 void CWallet::ListLockedCoins(std::vector<COutPoint>& vOutpts)
 {
+    AssertLockHeld(cs_wallet); // setLockedCoins
     for (std::set<COutPoint>::iterator it = setLockedCoins.begin();
          it != setLockedCoins.end(); it++) {
         COutPoint outpt = (*it);
@@ -1939,6 +1956,7 @@ void CWallet::ListLockedCoins(std::vector<COutPoint>& vOutpts)
 }
 
 void CWallet::GetKeyBirthTimes(std::map<CKeyID, int64_t> &mapKeyBirth) const {
+    AssertLockHeld(cs_wallet); // mapKeyMetadata
     mapKeyBirth.clear();
 
     // get birth times for keys with metadata
diff --git a/src/wallet.h b/src/wallet.h
index 8e879c5e1a..feb5cbf0c7 100644
--- a/src/wallet.h
+++ b/src/wallet.h
@@ -102,6 +102,11 @@ private:
     int64_t nLastResend;
 
 public:
+    /// Main wallet lock.
+    /// This lock protects all the fields added by CWallet
+    ///   except for:
+    ///      fFileBacked (immutable after instantiation)
+    ///      strWalletFile (immutable after instantiation)
     mutable CCriticalSection cs_wallet;
 
     bool fFileBacked;
@@ -151,10 +156,11 @@ public:
     int64_t nTimeFirstKey;
 
     // check whether we are allowed to upgrade (or already support) to the named feature
-    bool CanSupportFeature(enum WalletFeature wf) { return nWalletMaxVersion >= wf; }
+    bool CanSupportFeature(enum WalletFeature wf) { AssertLockHeld(cs_wallet); return nWalletMaxVersion >= wf; }
 
     void AvailableCoins(std::vector<COutput>& vCoins, bool fOnlyConfirmed=true, const CCoinControl *coinControl = NULL) const;
     bool SelectCoinsMinConf(int64_t nTargetValue, int nConfMine, int nConfTheirs, std::vector<COutput> vCoins, std::set<std::pair<const CWalletTx*,unsigned int> >& setCoinsRet, int64_t& nValueRet) const;
+
     bool IsLockedCoin(uint256 hash, unsigned int n) const;
     void LockCoin(COutPoint& output);
     void UnlockCoin(COutPoint& output);
@@ -171,7 +177,7 @@ public:
     // Load metadata (used by LoadWallet)
     bool LoadKeyMetadata(const CPubKey &pubkey, const CKeyMetadata &metadata);
 
-    bool LoadMinVersion(int nVersion) { nWalletVersion = nVersion; nWalletMaxVersion = std::max(nWalletMaxVersion, nVersion); return true; }
+    bool LoadMinVersion(int nVersion) { AssertLockHeld(cs_wallet); nWalletVersion = nVersion; nWalletMaxVersion = std::max(nWalletMaxVersion, nVersion); return true; }
 
     // Adds an encrypted key to the store, and saves it to disk.
     bool AddCryptedKey(const CPubKey &vchPubKey, const std::vector<unsigned char> &vchCryptedSecret);
@@ -320,6 +326,7 @@ public:
 
     unsigned int GetKeyPoolSize()
     {
+        AssertLockHeld(cs_wallet); // setKeyPool
         return setKeyPool.size();
     }
 
@@ -332,7 +339,7 @@ public:
     bool SetMaxVersion(int nVersion);
 
     // get the current wallet format (the oldest client version guaranteed to understand this wallet)
-    int GetVersion() { return nWalletVersion; }
+    int GetVersion() { AssertLockHeld(cs_wallet); return nWalletVersion; }
 
     /** Address book entry changed.
      * @note called with lock cs_wallet held.