diff --git a/controller/KissCount.cpp b/controller/KissCount.cpp
index 10109cc..d4e6f7a 100644
--- a/controller/KissCount.cpp
+++ b/controller/KissCount.cpp
@@ -74,9 +74,9 @@ void KissCount::UpdateOperation(struct operation op)
     _db->UpdateOperation(op);
 }
 
-void KissCount::AddOperation(struct operation op)
+wxString KissCount::AddOperation(struct operation op)
 {
-    _db->AddOperation(_user, op);
+    return _db->AddOperation(_user, op);
 }
 
 void KissCount::DeleteOperation(struct operation op)
@@ -89,18 +89,30 @@ void KissCount::SetAccountAmount(int month, int year, wxString accountId, double
   _db->SetAccountAmount(month, year, accountId, amount);
 }
 
-void KissCount::InsertAccount(struct Account ac)
+void KissCount::AddAccount(struct Account ac)
 {
-  _db->InsertAccount(_user, ac);
+  ac.id = _db->AddAccount(_user, ac);
+  _user->_accounts.push_back(ac);
 }
 
 void KissCount::UpdateAccount(struct Account ac)
 {
+  std::vector<Account>::iterator it;
+  int i;
+
   _db->UpdateAccount(ac);
+  for (i=0, it=_user->_accounts.begin(); it !=_user->_accounts.end(); it++, i++)
+    if (it->id == ac.id)
+      _user->_accounts[i] = ac;
 }
 
 void KissCount::DeleteAccount(struct Account ac)
 {
+  std::vector<Account>::iterator it;
+  int i;
+
   _db->DeleteAccount(ac);
-  _user->_accounts.erase(ac.id);
+  for (i=0, it=_user->_accounts.begin(); it !=_user->_accounts.end(); it++, i++)
+    if (it->id == ac.id)
+      _user->_accounts.erase(_user->_accounts.begin()+i);
 }
diff --git a/controller/KissCount.h b/controller/KissCount.h
index b765085..29769ee 100644
--- a/controller/KissCount.h
+++ b/controller/KissCount.h
@@ -22,10 +22,10 @@ class KissCount
   User* GetUser();
   double GetAccountAmount(wxString id, int month, int year);
   void UpdateOperation(struct operation op);
-  void AddOperation(struct operation op);
+  wxString AddOperation(struct operation op);
   void DeleteOperation(struct operation op);
   void SetAccountAmount(int month, int year, wxString accountId, double value);
-  void InsertAccount(struct Account ac);
+  void AddAccount(struct Account ac);
   void UpdateAccount(struct Account ac);
   void DeleteAccount(struct Account ac);
 
diff --git a/model/Database.cpp b/model/Database.cpp
index 3432727..015b052 100644
--- a/model/Database.cpp
+++ b/model/Database.cpp
@@ -148,7 +148,7 @@ User* Database::LoadUser(wxString name)
   wxString req;
   User* user;
   struct Account account;
-  std::map<wxString, Account>::iterator it;
+  std::vector<Account>::iterator it;
 
   req = _("SELECT * FROM user WHERE name='") + name + _("'"); 
 
@@ -176,18 +176,18 @@ User* Database::LoadUser(wxString name)
       account.number = set.GetAsString(_("number"));
       account.shared = set.GetBool(_("shared"));
       account._default = set.GetBool(_("default_account"));
-      user->_accounts[account.id] = account;
+      user->_accounts.push_back(account);
     }
   set.Finalize();
 
   if (!user->_accounts.empty())
     {
       it = user->_accounts.begin();
-      req = _("SELECT DISTINCT year FROM account_amount WHERE account IN('") + it->first;
+      req = _("SELECT DISTINCT year FROM account_amount WHERE account IN('") + it->id;
       it++;
       for (;it != user->_accounts.end(); it++)
 	{
-	  req += _("', '") + it->first ;
+	  req += _("', '") + it->id ;
 	}
       req += _("') ORDER BY year ASC");
 
@@ -223,17 +223,17 @@ void Database::LoadYear(User* user, int year)
 {
   wxSQLite3ResultSet set;
   wxString req;
-  std::map<wxString, Account>::iterator it;
+  std::vector<Account>::iterator it;
 
   if (user->_operations[year] == NULL)
     user->_operations[year] = new std::map<unsigned int, std::vector<operation> >();
 
   it = user->_accounts.begin();
-  req = _("SELECT * FROM operation WHERE account IN('") + it->first;
+  req = _("SELECT * FROM operation WHERE account IN('") + it->id;
   it++;
   for (;it != user->_accounts.end(); it++)
     {
-      req += _("', '") + it->first ;
+      req += _("', '") + it->id ;
     }
   req += _("') ORDER BY fix_cost DESC, year,month,day ASC");
 
@@ -306,9 +306,11 @@ void Database::UpdateOperation(struct operation op)
 
 }
 
-void Database::AddOperation(User* user, struct operation op)
+wxString Database::AddOperation(User* user, struct operation op)
 {
-    wxString req;
+  wxString req, res;
+    wxSQLite3ResultSet set;
+
     req = _("INSERT INTO operation ('user', 'account', 'year', 'month', 'day', 'amount', 'description', 'category', 'fix_cost') VALUES ('") ;
     req += user->_id + _("'");
     req += _(", '") + op.account + _("'");
@@ -324,7 +326,33 @@ void Database::AddOperation(User* user, struct operation op)
 	req += _(", '0'") ;
     req += _(")");
 	    
-    EXECUTE_SQL_UPDATE(req, );
+    EXECUTE_SQL_UPDATE(req, _("0"));
+
+    req = _("SELECT id FROM operation WHERE ");
+    req += _("user='") + user->_id + _("'");
+    req += _(" AND account='") + op.account + _("'");
+    req += _(" AND year='") + wxString::Format(_("%d"), op.year) + _("'");
+    req += _(" AND month='") + wxString::Format(_("%d"), op.month) + _("'");
+    req += _(" AND day='") + wxString::Format(_("%d"), op.day) + _("'");
+    req += _(" AND amount='") + wxString::Format(_("%.2lf"), op.amount) + _("'");
+    req += _(" AND description=\"") + op.description + _("\"");
+    req += _(" AND category='") + op.category + _("'");
+    if (op.fix_cost)
+	req += _(" AND fix_cost='1'") ;
+    else
+	req += _(" AND fix_cost='0'") ;
+    req += _("ORDER BY ID DESC") ;
+
+    EXECUTE_SQL_QUERY(req , set, _("0"));
+
+    if (set.NextRow())
+      res = set.GetAsString(_("id"));
+    else
+      res = _("0");
+
+    set.Finalize();
+
+    return res;
 }
 
 void Database::DeleteOperation(struct operation op)
@@ -347,9 +375,11 @@ void Database::SetAccountAmount(int month, int year, wxString accountId, double
     EXECUTE_SQL_UPDATE(req, );
 }
 
-void Database::InsertAccount(User* user, struct Account ac)
+wxString Database::AddAccount(User* user, struct Account ac)
 {
-    wxString req;
+  wxString req, res;
+  wxSQLite3ResultSet set;
+
     req = _("INSERT INTO account ('user', 'name', 'number', 'shared', 'default_account') VALUES ('") ;
     req += user->_id + _("'");
     req += _(", '") + ac.name + _("'");
@@ -364,7 +394,20 @@ void Database::InsertAccount(User* user, struct Account ac)
 	req += _(", '0'") ;
     req += _(")");
 	    
-    EXECUTE_SQL_UPDATE(req, );
+    EXECUTE_SQL_UPDATE(req, _("0"));
+
+    req = _("SELECT id FROM account WHERE name='") + ac.name + _("'") ;
+
+    EXECUTE_SQL_QUERY(req , set, _("0"));
+
+    if (set.NextRow())
+      res = set.GetAsString(_("id"));
+    else
+      res = _("0");
+
+    set.Finalize();
+
+    return res;
 }
 
 void Database::UpdateAccount(struct Account ac)
diff --git a/model/Database.h b/model/Database.h
index 186657d..35bc076 100644
--- a/model/Database.h
+++ b/model/Database.h
@@ -25,12 +25,12 @@ class Database
   void LoadYear(User* user, int year);
 
   void UpdateOperation(struct operation op);
-  void AddOperation(User* user, struct operation op);
+  wxString AddOperation(User* user, struct operation op);
   void DeleteOperation(struct operation op);
   double GetAccountAmount(wxString id, int month, int year);
   void SetAccountAmount(int month, int year, wxString accountId, double amount);
 
-  void InsertAccount(User* user, struct Account ac);
+  wxString AddAccount(User* user, struct Account ac);
   void UpdateAccount(struct Account ac);
   void DeleteAccount(struct Account ac);
 
diff --git a/model/User.cpp b/model/User.cpp
index a1d1c78..c28119b 100644
--- a/model/User.cpp
+++ b/model/User.cpp
@@ -33,17 +33,20 @@ wxString User::GetCategoryId(wxString catName)
 
 wxString User::GetAccountName(wxString accountId)
 {
-  if (_accounts.find(accountId) == _accounts.end())
+    std::vector<Account>::iterator it;
+    for (it=_accounts.begin(); it !=_accounts.end(); it++)
+	if (it->id == accountId)
+	    return it->name;
+
     return _("Unknown") ;
-  return _accounts[accountId].name;
 }
 
 wxString User::GetAccountId(wxString accountName)
 {
-    std::map<wxString, wxString>::iterator it;
-    for (it=_preferences._categories.begin(); it !=_preferences._categories.end(); it++)
-	if (it->second == accountName)
-	    return it->first;
+    std::vector<Account>::iterator it;
+    for (it=_accounts.begin(); it !=_accounts.end(); it++)
+	if (it->name == accountName)
+	    return it->id;
 
     return _("0") ;
 }
diff --git a/model/User.h b/model/User.h
index ac88a7c..800b110 100644
--- a/model/User.h
+++ b/model/User.h
@@ -34,7 +34,7 @@ public:
   wxString _id;
   wxString _name;
   wxString _password;
-  std::map<wxString, Account> _accounts;
+  std::vector<Account> _accounts;
   std::map<unsigned int, std::map<unsigned int, std::vector<operation> >* > _operations;
   Preferences _preferences;
 
diff --git a/view/AccountPanel.cpp b/view/AccountPanel.cpp
index 0758af5..a6807da 100644
--- a/view/AccountPanel.cpp
+++ b/view/AccountPanel.cpp
@@ -21,7 +21,7 @@ AccountPanel::AccountPanel(KissCount* kiss, wxUI *parent) : wxPanel(&(*parent)),
       int i ;
       DEFAULT_FONT(font);
       User* user = _kiss->GetUser();
-      std::map<wxString, Account>::iterator accountIt;
+      std::vector<Account>::iterator accountIt;
       std::map<wxString, wxString>::iterator it;
       wxColour categoryColors[] = {wxColour(0x00, 0x45, 0x86),
 				   wxColour(0xFF, 0x3E, 0x0E),
@@ -41,12 +41,12 @@ AccountPanel::AccountPanel(KissCount* kiss, wxUI *parent) : wxPanel(&(*parent)),
 
       _pie = new PiePlot();
 
-      _accounts = new wxString[user->_accounts.size()];
+      _accounts = new wxString[user->GetAccountsNumber()];
       for (i=0, 
 	     accountIt = user->_accounts.begin();
 	   accountIt != user->_accounts.end();
 	   accountIt++, i++)
-	_accounts[i] = user->_accounts[accountIt->first].name;
+	_accounts[i] = accountIt->name;
 
       _categories = new wxString[user->GetCategoriesNumber()] ;
       for(i=0, it = user->_preferences._categories.begin(); it != user->_preferences._categories.end(); it++, i++)
@@ -319,7 +319,7 @@ void AccountPanel::InsertOperation(User* user, operation* op, int line, bool fix
 
     _grid->SetCellEditor(line, DEBIT, new wxGridCellFloatEditor(-1, 2));
     _grid->SetCellEditor(line, CREDIT, new wxGridCellFloatEditor(-1, 2));
-    wxGridCellChoiceEditor* accountEditor = new wxGridCellChoiceEditor(user->_accounts.size(), _accounts, false);
+    wxGridCellChoiceEditor* accountEditor = new wxGridCellChoiceEditor(user->GetAccountsNumber(), _accounts, false);
     _grid->SetCellEditor(line, ACCOUNT, accountEditor);
     // Remove Fix category
     wxGridCellChoiceEditor* categoryEditor = new wxGridCellChoiceEditor(user->GetCategoriesNumber()-1, _categories+1, false);
@@ -404,9 +404,8 @@ void AccountPanel::InsertOperation(User* user, operation* op, int line, bool fix
 
 void AccountPanel::InitAccountsGrid(User* user, int month, int year)
 {
-  std::map<wxString, Account>::iterator it;
+  std::vector<Account>::iterator it;
   int curLine = 0;
-  Account account ;
   double value;
   int i, a;
   DEFAULT_FONT(font);
@@ -416,19 +415,17 @@ void AccountPanel::InitAccountsGrid(User* user, int month, int year)
   for (i=0, it = user->_accounts.begin(); it != user->_accounts.end(); i++, it++, curLine++)
     {
       _accountsGrid->AppendRows();
-      account = user->_accounts[it->first];
 
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_NUMBER, account.number);
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_NAME, account.name);
-      value = _kiss->GetAccountAmount(it->first, month, year);
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_NUMBER, it->number);
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_NAME, it->name);
+      value = _kiss->GetAccountAmount(it->id, month, year);
       _accountsGrid->SetCellValue(curLine, ACCOUNT_INIT, wxString::Format(wxT("%.2lf"), value));
       _accountsGrid->SetCellEditor(curLine, ACCOUNT_INIT, new wxGridCellFloatEditor(-1, 2));
       for (a=0; a<NUMBER_COLS_ACCOUNTS; a++)
 	_accountsGrid->SetReadOnly(curLine, a, a != ACCOUNT_INIT);
       _accountsGrid->SetCellFont(curLine, ACCOUNT_CUR, font);
 
-      _accountsIndexes[it->first] = i;
-      _accountsInitValues[it->first] = value;
+      _accountsInitValues[it->id] = value;
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_INIT, wxALIGN_RIGHT, wxALIGN_CENTRE);
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_CUR, wxALIGN_RIGHT, wxALIGN_CENTRE);
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_FINAL, wxALIGN_RIGHT, wxALIGN_CENTRE);
@@ -447,6 +444,7 @@ void AccountPanel::UpdateStats()
   std::map<wxString, double> curAccountAmount, finalAccountAmount;
   std::map<wxString, double>::iterator doubleIt;
   std::map<wxString, int>::iterator intIt;
+  std::vector<Account>::iterator accountIt;
 
   curDate.SetToCurrent();
 
@@ -498,13 +496,12 @@ void AccountPanel::UpdateStats()
   for(i=0; i<user->GetCategoriesNumber()+1; i++)
     _statsGrid->SetCellValue(CATS_STATS+i, 1, wxString::Format(wxT("%.2lf"), _categoriesValues[i]));
 
-  for (intIt=_accountsIndexes.begin(); intIt!=_accountsIndexes.end(); intIt++)
+  for (i=0, accountIt=user->_accounts.begin(); accountIt!=user->_accounts.end(); accountIt++, i++)
     {
-      i = _accountsIndexes[intIt->first];
-      value = curAccountAmount[intIt->first];
+      value = curAccountAmount[accountIt->id];
       _accountsGrid->SetCellValue(i, ACCOUNT_CUR, wxString::Format(wxT("%.2lf"), value));
       _accountsGrid->SetCellTextColour(i, ACCOUNT_CUR, (value >= 0.0) ? wxColor(0x00, 0x00, 0x00) : wxColor(0xFF, 0x00, 0x00));
-      value = finalAccountAmount[intIt->first];
+      value = finalAccountAmount[accountIt->id];
       _accountsGrid->SetCellValue(i, ACCOUNT_FINAL, wxString::Format(wxT("%.2lf"), value));
     }
 
@@ -653,13 +650,14 @@ void AccountPanel::OnOperationModified(wxGridEvent& event)
       }
       need_insertion = true;
       fix_op = true;
+      new_op.fix_cost = true;
 
       for(i=0; i<NUMBER_COLS_OPS; i++)
 	{
 	  if (i == CATEGORY) continue;
 	  _grid->SetCellValue(event.GetRow(), i, _(""));
 	}
-      _kiss->AddOperation(new_op);
+      new_op.id = _kiss->AddOperation(new_op);
     }
   // Modify an operation
   else if (row <= user->GetOperationsNumber(_curMonth, _curYear))
@@ -697,12 +695,14 @@ void AccountPanel::OnOperationModified(wxGridEvent& event)
 	return ;
       }
       need_insertion = true;
+      fix_op = false;
+      new_op.fix_cost = false;
 
       for(i=0; i<NUMBER_COLS_OPS; i++)
 	{
 	  _grid->SetCellValue(event.GetRow(), i, _(""));
 	}
-      _kiss->AddOperation(new_op);
+      new_op.id = _kiss->AddOperation(new_op);
     }
 
   if (need_insertion)
diff --git a/view/AccountPanel.h b/view/AccountPanel.h
index 1b506eb..d7be19f 100644
--- a/view/AccountPanel.h
+++ b/view/AccountPanel.h
@@ -48,7 +48,7 @@ private:
   wxGrid *_statsGrid, *_accountsGrid;
   PiePlot* _pie;
   double *_categoriesValues;
-  std::map<wxString, int> _categoriesIndexes, _accountsIndexes;
+  std::map<wxString, int> _categoriesIndexes;
   std::vector<operation>* _curOperations;
   int _curMonth, _curYear;
   wxString* _categories, *_accounts;
diff --git a/view/PreferencesPanel.cpp b/view/PreferencesPanel.cpp
index 53b126a..d8376e4 100644
--- a/view/PreferencesPanel.cpp
+++ b/view/PreferencesPanel.cpp
@@ -80,7 +80,7 @@ PreferencesPanel::PreferencesPanel(KissCount* kiss, wxUI *parent) : wxPanel(&(*p
 
 void PreferencesPanel::InitAccounts(User* user)
 {
-    std::map<wxString, Account>::iterator it;
+    std::vector<Account>::iterator it;
     int curLine = 0;
     Account account ;
     DEFAULT_FONT(font);
@@ -97,10 +97,9 @@ void PreferencesPanel::InitAccounts(User* user)
   for (it = user->_accounts.begin(); it != user->_accounts.end(); it++, curLine++)
     {
       _accountsGrid->AppendRows();
-      account = user->_accounts[it->first];
 
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_NAME, account.name);
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_NUMBER, account.number);
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_NAME, it->name);
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_NUMBER, it->number);
 
       _accountsGrid->SetCellRenderer(curLine, ACCOUNT_SHARED, new wxGridCellBoolRenderer ());
       _accountsGrid->SetCellEditor(curLine, ACCOUNT_SHARED, new wxGridCellBoolEditor ());
@@ -108,13 +107,12 @@ void PreferencesPanel::InitAccounts(User* user)
       _accountsGrid->SetCellEditor(curLine, ACCOUNT_DEFAULT, new wxGridCellBoolEditor ());
       _accountsGrid->SetCellRenderer(curLine, ACCOUNT_DELETE, new wxGridCellBoolRenderer ());
       _accountsGrid->SetCellEditor(curLine, ACCOUNT_DELETE, new wxGridCellBoolEditor ());
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_SHARED, (account.shared)?_("1"):_("0"));
-      _accountsGrid->SetCellValue(curLine, ACCOUNT_DEFAULT, (account._default)?_("1"):_("0"));
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_SHARED, (it->shared)?_("1"):_("0"));
+      _accountsGrid->SetCellValue(curLine, ACCOUNT_DEFAULT, (it->_default)?_("1"):_("0"));
       
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_SHARED, wxALIGN_CENTRE, wxALIGN_CENTRE);
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_DEFAULT, wxALIGN_CENTRE, wxALIGN_CENTRE);
       _accountsGrid->SetCellAlignment(curLine, ACCOUNT_DELETE, wxALIGN_CENTRE, wxALIGN_CENTRE);
-      _accountsIndexes[curLine] = account.id;
     }
 
   _accountsGrid->AutoSizeColumns(true);    
@@ -221,18 +219,17 @@ void PreferencesPanel::OnAccountModified(wxGridEvent& event)
 
   if (col == ACCOUNT_DEFAULT)
     {
-      new_account.id = _accountsIndexes[row];
+      new_account.id = user->_accounts[row].id;
 
       for (i=0; i<user->GetAccountsNumber(); i++)
 	{
-	  if (i != col)
+	  if (i != row)
 	    {
-	      account = user->_accounts[_accountsIndexes[i]];
+	      account = user->_accounts[i];
 	      if (account._default)
 		{
 		  account._default = false;
 		  _kiss->UpdateAccount(account);
-		  user->_accounts[_accountsIndexes[i]] = account;
 		  _accountsGrid->SetCellValue(i, ACCOUNT_DEFAULT, _(""));
 		  break;
 		}
@@ -245,7 +242,7 @@ void PreferencesPanel::OnAccountModified(wxGridEvent& event)
   // Account modification
   if (user->GetAccountsNumber() && row < user->GetAccountsNumber())
     {
-      new_account.id = _accountsIndexes[row];
+      new_account.id = user->_accounts[row].id;
 
       if (col == ACCOUNT_DELETE)
 	{
@@ -275,6 +272,14 @@ void PreferencesPanel::OnAccountModified(wxGridEvent& event)
 	  return ;
 	}
 
+      if (user->GetAccountId(new_account.name) != _("0"))
+	{
+	  wxMessageDialog dialog(_wxUI, _("Account ")+new_account.name+_(" already exists"), _("Error"), wxOK);
+	  dialog.ShowModal();
+	  inModification = false;
+	  return ;
+	}
+
       _accountsGrid->SetCellRenderer(row, ACCOUNT_SHARED, new wxGridCellBoolRenderer ());
       _accountsGrid->SetCellEditor(row, ACCOUNT_SHARED, new wxGridCellBoolEditor ());
       _accountsGrid->SetCellRenderer(row, ACCOUNT_DEFAULT, new wxGridCellBoolRenderer ());
@@ -303,7 +308,7 @@ void PreferencesPanel::OnAccountModified(wxGridEvent& event)
       _accountsGrid->SetReadOnly(row+1, ACCOUNT_DELETE, true);
       _wxUI->Layout();
 
-      _kiss->InsertAccount(new_account);
+      _kiss->AddAccount(new_account);
     }
 
   inModification = false;
diff --git a/view/PreferencesPanel.h b/view/PreferencesPanel.h
index 6d8ad10..3570dac 100644
--- a/view/PreferencesPanel.h
+++ b/view/PreferencesPanel.h
@@ -30,7 +30,7 @@ private:
   wxUI* _wxUI;
   wxGrid* _accountsGrid;
   wxGrid* _categoriesGrid;
-  std::map<int, wxString> _categoriesIndexes, _accountsIndexes;
+  std::map<int, wxString> _categoriesIndexes;
 
   void InitAccounts(User* user);
   void InitCategories(User* user);