diff --git a/ClientCommand.cpp b/ClientCommand.cpp
index 980174a9..28fd6d83 100644
--- a/ClientCommand.cpp
+++ b/ClientCommand.cpp
@@ -583,7 +583,7 @@ void CClient::UserCommand(CString& sLine) {
 			set<CModInfo> ssGlobalMods;
 			CZNC::Get().GetModules().GetAvailableMods(ssGlobalMods, true);
 
-			if (!ssGlobalMods.size()) {
+			if (ssGlobalMods.empty()) {
 				PutStatus("No global modules available.");
 			} else {
 				PutStatus("Global modules:");
diff --git a/User.cpp b/User.cpp
index 5ec675ea..08f799a4 100644
--- a/User.cpp
+++ b/User.cpp
@@ -733,7 +733,7 @@ CChan* CUser::FindChan(const CString& sName) const {
 
 void CUser::JoinChans() {
 	// Avoid divsion by zero, it's bad!
-	if (m_vChans.size() == 0)
+	if (m_vChans.empty())
 		return;
 
 	// We start at a random offset into the channel list so that if your
@@ -962,7 +962,7 @@ CString CUser::GetLocalIP() {
 		return pIRCSock->GetLocalIP();
 	}
 
-	if (m_vClients.size()) {
+	if (!m_vClients.empty()) {
 		return m_vClients[0]->GetLocalIP();
 	}
 
@@ -1117,7 +1117,7 @@ CString CUser::GetCurNick() const {
 		return pIRCSock->GetNick();
 	}
 
-	if (m_vClients.size()) {
+	if (!m_vClients.empty()) {
 		return m_vClients[0]->GetNick();
 	}
 
diff --git a/znc.cpp b/znc.cpp
index 9b222c54..325988aa 100644
--- a/znc.cpp
+++ b/znc.cpp
@@ -192,7 +192,7 @@ bool CZNC::HandleUserDeletion()
 	map<CString, CUser*>::iterator it;
 	map<CString, CUser*>::iterator end;
 
-	if (m_msDelUsers.size() == 0)
+	if (m_msDelUsers.empty())
 		return false;
 
 	end = m_msDelUsers.end();
@@ -683,7 +683,7 @@ bool CZNC::WriteNewConfig(const CString& sConfigFile) {
 	GetModules().GetAvailableMods(ssGlobalMods, true);
 	size_t uNrOtherGlobalMods = FilterUncommonModules(ssGlobalMods);
 
-	if (ssGlobalMods.size()) {
+	if (!ssGlobalMods.empty()) {
 		CUtils::PrintMessage("");
 		CUtils::PrintMessage("-- Global Modules --");
 		CUtils::PrintMessage("");
@@ -1020,7 +1020,7 @@ bool CZNC::RehashConfig(CString& sError)
 
 	// Rehashing failed, try to recover
 	CString s;
-	while (m_msDelUsers.size()) {
+	while (!m_msDelUsers.empty()) {
 		AddUser(m_msDelUsers.begin()->second, s);
 		m_msDelUsers.erase(m_msDelUsers.begin());
 	}
@@ -1078,7 +1078,7 @@ bool CZNC::DoRehash(CString& sError)
 	m_vsMotd.clear();
 
 	// Delete all listeners
-	while (m_vpListeners.size()) {
+	while (!m_vpListeners.empty()) {
 		delete m_vpListeners[0];
 		m_vpListeners.erase(m_vpListeners.begin());
 	}
@@ -1685,13 +1685,13 @@ bool CZNC::DoRehash(CString& sError)
 		delete pUser;
 	}
 
-	if (m_msUsers.size() == 0) {
+	if (m_msUsers.empty()) {
 		sError = "You must define at least one user in your config.";
 		CUtils::PrintError(sError);
 		return false;
 	}
 
-	if (m_vpListeners.size() == 0) {
+	if (m_vpListeners.empty()) {
 		sError = "You must supply at least one Listen port in your config.";
 		CUtils::PrintError(sError);
 		return false;