diff --git a/engine/accountlock.go b/engine/accountlock.go
index 27349135b..6ea5c104d 100644
--- a/engine/accountlock.go
+++ b/engine/accountlock.go
@@ -68,3 +68,21 @@ func (cm *AccountLock) Guard(name string, handler func() (float64, error)) (repl
 	<-lock
 	return
 }
+
+func (cm *AccountLock) GuardMany(names []string, handler func() (float64, error)) (reply float64, err error) {
+	for _, name := range names {
+		cm.RLock()
+		lock, exists := AccLock.queue[name]
+		cm.RUnlock()
+		if !exists {
+			cm.Lock()
+			lock = make(chan bool, 1)
+			AccLock.queue[name] = lock
+			cm.Unlock()
+		}
+		lock <- true
+		reply, err = handler()
+		<-lock
+	}
+	return
+}
diff --git a/engine/sharedgroup.go b/engine/sharedgroup.go
index 632544e1c..7980fea96 100644
--- a/engine/sharedgroup.go
+++ b/engine/sharedgroup.go
@@ -18,6 +18,18 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>
 
 package engine
 
+import (
+	"math"
+	"math/rand"
+	"time"
+)
+
+const (
+	STRATEGY_LOWEST_FIRST  = "*lowest_first"
+	STRATEGY_HIGHEST_FIRST = "*highest_first"
+	STRATEGY_RANDOM        = "*random"
+)
+
 type SharedGroup struct {
 	Id          string
 	Strategy    string
@@ -26,3 +38,46 @@ type SharedGroup struct {
 	Weight      float64
 	Members     []string
 }
+
+func (sg *SharedGroup) GetMembersExceptUser(ubId string) []string {
+	for i, m := range sg.Members {
+		if m == ubId {
+			a := make([]string, len(sg.Members))
+			copy(a, sg.Members)
+			a[i], a = a[len(a)-1], a[:len(a)-1]
+			return a
+		}
+	}
+	return sg.Members
+}
+
+func (sg *SharedGroup) PopBalanceByStrategy(balanceChain *BalanceChain) (bal *Balance) {
+	bc := *balanceChain
+	if len(bc) == 0 {
+		return
+	}
+	index := 0
+	switch sg.Strategy {
+	case STRATEGY_RANDOM:
+		rand.Seed(time.Now().Unix())
+		index = rand.Intn(len(bc))
+	case STRATEGY_LOWEST_FIRST:
+		minVal := math.MaxFloat64
+		for i, b := range bc {
+			if b.Value < minVal {
+				minVal = b.Value
+				index = i
+			}
+		}
+	case STRATEGY_HIGHEST_FIRST:
+		maxVal := math.SmallestNonzeroFloat64
+		for i, b := range bc {
+			if b.Value > maxVal {
+				maxVal = b.Value
+				index = i
+			}
+		}
+	}
+	bal, bc[index], *balanceChain = bc[index], bc[len(bc)-1], bc[:len(bc)-1]
+	return
+}
diff --git a/engine/sharedgroup_test.go b/engine/sharedgroup_test.go
new file mode 100644
index 000000000..384570dce
--- /dev/null
+++ b/engine/sharedgroup_test.go
@@ -0,0 +1,75 @@
+/*
+Rating system designed to be used in VoIP Carriers World
+Copyright (C) 2013 ITsysCOM
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+*/
+
+package engine
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestSharedGroupGetMembersExcept(t *testing.T) {
+	sg := &SharedGroup{
+		Members: []string{"1", "2", "3"},
+	}
+	a1 := sg.GetMembersExceptUser("1")
+	a2 := sg.GetMembersExceptUser("2")
+	a3 := sg.GetMembersExceptUser("3")
+	if !reflect.DeepEqual(a1, []string{"3", "2"}) ||
+		!reflect.DeepEqual(a2, []string{"1", "3"}) ||
+		!reflect.DeepEqual(a3, []string{"1", "2"}) {
+		t.Error("Error getting shared group members: ", a1, a2, a3)
+	}
+
+}
+
+func TestSharedPopBalanceByStrategyLow(t *testing.T) {
+	bc := BalanceChain{
+		&Balance{Value: 2.0},
+		&Balance{Value: 1.0},
+		&Balance{Value: 3.0},
+	}
+	sg := &SharedGroup{Strategy: STRATEGY_LOWEST_FIRST}
+	b := sg.PopBalanceByStrategy(&bc)
+	if b.Value != 1.0 {
+		t.Error("Error popping the right balance according to strategy: ", b, bc)
+	}
+	if len(bc) != 2 ||
+		bc[0].Value != 2.0 ||
+		bc[1].Value != 3.0 {
+		t.Error("Error removing balance from chain: ", bc)
+	}
+}
+
+func TestSharedPopBalanceByStrategyHigh(t *testing.T) {
+	bc := BalanceChain{
+		&Balance{Value: 2.0},
+		&Balance{Value: 1.0},
+		&Balance{Value: 3.0},
+	}
+	sg := &SharedGroup{Strategy: STRATEGY_HIGHEST_FIRST}
+	b := sg.PopBalanceByStrategy(&bc)
+	if b.Value != 3.0 {
+		t.Error("Error popping the right balance according to strategy: ", b, bc)
+	}
+	if len(bc) != 2 ||
+		bc[0].Value != 2.0 ||
+		bc[1].Value != 1.0 {
+		t.Error("Error removing balance from chain: ", bc)
+	}
+}
diff --git a/engine/userbalance.go b/engine/userbalance.go
index 824a5cff1..e82150589 100644
--- a/engine/userbalance.go
+++ b/engine/userbalance.go
@@ -189,31 +189,7 @@ func (ub *UserBalance) debitCreditBalance(cc *CallCost, count bool) error {
 		} else {
 			// chack if it's shared
 			if balance.SharedGroup != "" {
-				sharedGroup, err := accountingStorage.GetSharedGroup(balance.SharedGroup, false)
-				if err != nil {
-					Logger.Warning(fmt.Sprintf("Could not get shared group: %s", balance.SharedGroup))
-					continue
-				}
-				for _, ubId := range sharedGroup.Members {
-					if ubId == ub.Id { // skip the initiating user
-						continue
-					}
-					AccLock.Guard(ubId, func() (float64, error) {
-						nUb, err := accountingStorage.GetUserBalance(ubId)
-						if err != nil {
-							Logger.Warning(fmt.Sprintf("Could not get user balance: %s", ubId))
-						}
-						sharedMinuteBalances := nUb.getBalancesForPrefix(cc.Destination, nUb.BalanceMap[MINUTES+cc.Direction], balance.SharedGroup)
-						sharedMoneyBalances := nUb.getBalancesForPrefix(cc.Destination, nUb.BalanceMap[CREDIT+cc.Direction], balance.SharedGroup)
-						for _, sharedBalance := range sharedMinuteBalances {
-							// FIXME: insert money balances after users balances
-              allMoneyBalances := append(usefulMoneyBalances, sharedMoneyBalances)
-							sharedBalance.DebitMinutes(cc, count, nUb, allMoneyBalances)
-							// FIXME: save nUb
-						}
-						return 0, nil
-					})
-				}
+				ub.debitFromSharedBalances(balance.SharedGroup, cc, usefulMoneyBalances, count)
 			}
 		}
 	}
@@ -265,6 +241,35 @@ func (ub *UserBalance) debitCreditBalance(cc *CallCost, count bool) error {
 	return returnError
 }
 
+func (ub *UserBalance) debitFromSharedBalances(sharedGroupName string, cc *CallCost, moneyBalances BalanceChain, count bool) {
+	sharedGroup, err := accountingStorage.GetSharedGroup(sharedGroupName, false)
+	if err != nil {
+		Logger.Warning(fmt.Sprintf("Could not get shared group: %s", sharedGroup))
+		return
+	}
+	sharingMembers := sharedGroup.GetMembersExceptUser(ub.Id)
+	AccLock.GuardMany(sharingMembers, func() (float64, error) {
+		for _, ubId := range sharingMembers {
+			if ubId == ub.Id { // skip the initiating user
+				continue
+			}
+
+			nUb, err := accountingStorage.GetUserBalance(ubId)
+			if err != nil {
+				Logger.Warning(fmt.Sprintf("Could not get user balance: %s", ubId))
+			}
+			sharedMinuteBalances := nUb.getBalancesForPrefix(cc.Destination, nUb.BalanceMap[MINUTES+cc.Direction], sharedGroupName)
+			sharedMoneyBalances := nUb.getBalancesForPrefix(cc.Destination, nUb.BalanceMap[CREDIT+cc.Direction], sharedGroupName)
+			for _, sharedBalance := range sharedMinuteBalances {
+				allMoneyBalances := append(moneyBalances, sharedMoneyBalances...)
+				sharedBalance.DebitMinutes(cc, count, nUb, allMoneyBalances)
+				accountingStorage.SetUserBalance(nUb)
+			}
+		}
+		return 0, nil
+	})
+}
+
 func (ub *UserBalance) GetDefaultMoneyBalance(direction string) *Balance {
 	for _, balance := range ub.BalanceMap[CREDIT+direction] {
 		if balance.IsDefault() {