diff --git a/owlps-positioner/building.cc b/owlps-positioner/building.cc
index 1a95214..bf45b88 100644
--- a/owlps-positioner/building.cc
+++ b/owlps-positioner/building.cc
@@ -61,7 +61,7 @@ Building::~Building()
  */
 void Building::add_area(const Area *const area)
 {
-  if (area == NULL)
+  if (!area)
     return ;
 
   string area_name = area->get_name() ;
diff --git a/owlps-positioner/building.hh b/owlps-positioner/building.hh
index 1a24a3d..8d4b354 100644
--- a/owlps-positioner/building.hh
+++ b/owlps-positioner/building.hh
@@ -112,7 +112,7 @@ inline void Building::set_name(const std::string &_name)
  */
 inline void Building::add_waypoint(Waypoint *const wp)
 {
-  if (wp != NULL)
+  if (wp)
     waypoints.insert(wp) ;
 }
 
diff --git a/owlps-positioner/calibrationrequest.hh b/owlps-positioner/calibrationrequest.hh
index 5c74ce5..b877b44 100644
--- a/owlps-positioner/calibrationrequest.hh
+++ b/owlps-positioner/calibrationrequest.hh
@@ -126,7 +126,7 @@ public:
 
     PosUtil::hash_combine(seed, static_cast<Request>(source)) ;
     PosUtil::hash_combine(seed, source.get_direction()) ;
-    if (source.get_reference_point() != NULL)
+    if (source.get_reference_point())
       PosUtil::hash_combine(seed, *source.get_reference_point()) ;
 
     return seed ;
diff --git a/owlps-positioner/input.cc b/owlps-positioner/input.cc
index b43409c..9cb20aa 100644
--- a/owlps-positioner/input.cc
+++ b/owlps-positioner/input.cc
@@ -147,7 +147,7 @@ const Request& Input::get_next_request() const
   /* If the request is a calibration request, add it to the Stock */
   CalibrationRequest *calibration_request =
     dynamic_cast<CalibrationRequest*>(const_cast<Request*>(&request)) ;
-  if (calibration_request != NULL)
+  if (calibration_request)
     {
       if (Configuration::bool_value(
             "positioning.accept-new-calibration-requests"))
@@ -183,7 +183,7 @@ const Request& Input::get_next_request() const
 
 bool Input::eof() const
 {
-  if (medium == NULL)
+  if (!medium)
     throw null_input_medium() ;
   return medium->eof() ;
 }
diff --git a/owlps-positioner/inputdatareader.cc b/owlps-positioner/inputdatareader.cc
index 6724dc1..4dba41e 100644
--- a/owlps-positioner/inputdatareader.cc
+++ b/owlps-positioner/inputdatareader.cc
@@ -255,7 +255,7 @@ void InputDataReader::read_from_reference_points_media()
           CalibrationRequest *calibration_request =
             dynamic_cast<CalibrationRequest*>(
               const_cast<Request*>(&request)) ;
-          if (calibration_request == NULL)
+          if (!calibration_request)
             cerr << "Warning! Invalid calibration request at line "
                  << (*i)->get_current_line_nb() << endl ;
           else
diff --git a/owlps-positioner/inputmedium.cc b/owlps-positioner/inputmedium.cc
index bd54a6d..b1e8a59 100644
--- a/owlps-positioner/inputmedium.cc
+++ b/owlps-positioner/inputmedium.cc
@@ -73,7 +73,7 @@ const Request& InputMedium::get_next_request()
 
 void InputMedium::clear_current_request()
 {
-  if (dynamic_cast<CalibrationRequest*>(current_request) == NULL)
+  if (! dynamic_cast<CalibrationRequest*>(current_request))
     current_request->clear() ;
   else
     {
@@ -164,7 +164,7 @@ void InputMedium::current_request_to_calibration_request(
 {
   CalibrationRequest *calibration_request =
     dynamic_cast<CalibrationRequest*>(current_request) ;
-  if (calibration_request != NULL)
+  if (calibration_request)
     {
       calibration_request->set_reference_point(
         const_cast<ReferencePoint*>(reference_point)) ;
diff --git a/owlps-positioner/measurement.hh b/owlps-positioner/measurement.hh
index 1ddd496..8f7446f 100644
--- a/owlps-positioner/measurement.hh
+++ b/owlps-positioner/measurement.hh
@@ -241,7 +241,7 @@ inline bool Measurement::operator!=(const Measurement &m) const
 inline Measurement::operator bool() const
 {
   return
-    cp != NULL ||
+    cp ||
     ! ss_list.empty() ;
 }
 
diff --git a/owlps-positioner/outputtcpsocketevaal.cc b/owlps-positioner/outputtcpsocketevaal.cc
index f67527d..ccdd68b 100644
--- a/owlps-positioner/outputtcpsocketevaal.cc
+++ b/owlps-positioner/outputtcpsocketevaal.cc
@@ -117,7 +117,7 @@ int OutputTCPSocketEvAAL::
 area_of_interest_number(const Point3D &position) const
 {
   const Area *const area = Stock::in_which_area_is(position) ;
-  if (area == NULL)
+  if (!area)
     return 0 ;
 
   int aoi_number = 0 ;
diff --git a/owlps-positioner/realposition.cc b/owlps-positioner/realposition.cc
index 761f037..737d825 100644
--- a/owlps-positioner/realposition.cc
+++ b/owlps-positioner/realposition.cc
@@ -25,7 +25,7 @@ Result RealPosition::compute(const Request &request)
   const CalibrationRequest *calibration_request =
     dynamic_cast<const CalibrationRequest*>(&request) ;
 
-  if (calibration_request != NULL)
+  if (calibration_request)
     coordinates = static_cast<Point3D*>(
                     calibration_request->get_reference_point()) ;
   else
diff --git a/owlps-positioner/referencepoint.cc b/owlps-positioner/referencepoint.cc
index e5d7b75..388aac0 100644
--- a/owlps-positioner/referencepoint.cc
+++ b/owlps-positioner/referencepoint.cc
@@ -163,7 +163,7 @@ bool ReferencePoint::delete_generated_requests(void)
       assert(*r) ;
       unordered_map<std::string, CapturePoint>::const_iterator cp ;
 
-      if ((*r)->get_mobile() == NULL)
+      if (! (*r)->get_mobile())
         goto delete_request ;
 
       // Check if the request was sent by a CP
diff --git a/owlps-positioner/referencepoint.hh b/owlps-positioner/referencepoint.hh
index 4d1a26e..c7df183 100644
--- a/owlps-positioner/referencepoint.hh
+++ b/owlps-positioner/referencepoint.hh
@@ -131,7 +131,7 @@ std::vector<CalibrationRequest*>& ReferencePoint::get_requests() const
  */
 inline void ReferencePoint::add_request(const CalibrationRequest *r)
 {
-  if (r != NULL)
+  if (r)
     requests.push_back(const_cast<CalibrationRequest*>(r)) ;
 }
 
diff --git a/owlps-positioner/request.cc b/owlps-positioner/request.cc
index 58ee791..a08c3c1 100644
--- a/owlps-positioner/request.cc
+++ b/owlps-positioner/request.cc
@@ -219,7 +219,7 @@ const string Request::to_csv() const
 
   csv_line << aggregation_csv_format << ';' ;
 
-  if (mobile != NULL)
+  if (mobile)
     csv_line << mobile->get_mac_addr() ;
 
   csv_line
@@ -230,7 +230,7 @@ const string Request::to_csv() const
 
   const CalibrationRequest *calibration_request =
     dynamic_cast<const CalibrationRequest*>(this) ;
-  if (calibration_request == NULL)
+  if (!calibration_request)
     csv_line << "0;0;0;0" ;
   else
     {
@@ -262,7 +262,7 @@ ostream& operator<<(ostream &os, const Request &r)
   os << "Type: " << static_cast<uint_fast16_t>(r.type)
      << ", Number of packets sent: " << r.nb_packets
      << ", Mobile: "
-     << (r.mobile != NULL ? r.mobile->get_mac_addr() : "Unknown_Mobile")
+     << (r.mobile ? r.mobile->get_mac_addr() : "Unknown_Mobile")
      << ":" ;
 
   // List of Measurements
diff --git a/owlps-positioner/request.hh b/owlps-positioner/request.hh
index a7f633c..02002b5 100644
--- a/owlps-positioner/request.hh
+++ b/owlps-positioner/request.hh
@@ -245,7 +245,7 @@ inline bool Request::operator!=(const Request &comp) const
 inline Request::operator bool() const
 {
   return
-    mobile != NULL ||
+    mobile ||
     time_sent ||
     ! measurements.empty() ;
 }
diff --git a/owlps-positioner/result.cc b/owlps-positioner/result.cc
index 743c25f..ba411f2 100644
--- a/owlps-positioner/result.cc
+++ b/owlps-positioner/result.cc
@@ -48,7 +48,7 @@ Result::Result(const Request *const _request,
 string Result::in_which_area() const
 {
   const Area *area = Stock::in_which_area_is(position) ;
-  if (area == NULL)
+  if (!area)
     return "" ;
 
   return area->get_name() ;
@@ -118,7 +118,7 @@ const string Result::to_csv() const
       << ';' ;
 
   const Area *const area = Stock::in_which_area_is(position) ;
-  if (area != NULL)
+  if (area)
     csv_line << area->get_name() ;
 
   return csv_line.str() ;
diff --git a/owlps-positioner/resultlist.cc b/owlps-positioner/resultlist.cc
index c12615b..20a6218 100644
--- a/owlps-positioner/resultlist.cc
+++ b/owlps-positioner/resultlist.cc
@@ -89,9 +89,9 @@ const string ResultList::to_csv() const
 {
   ostringstream csv_line ;
 
-  if (request != NULL)
+  if (request)
     {
-      if (request->get_mobile() != NULL)
+      if (request->get_mobile())
         csv_line << request->get_mobile()->get_mac_addr() ;
       csv_line
           << ';' << static_cast<uint_fast16_t>(request->get_type())
@@ -110,7 +110,7 @@ const string ResultList::to_csv() const
 
 ostream& operator<<(ostream &os, const ResultList &r)
 {
-  if (r.request == NULL)
+  if (!r.request)
     os << "For an unknown request:\n" ;
   else
     os << "For the following request: " << *(r.request) << '\n' ;
diff --git a/owlps-positioner/stock.cc b/owlps-positioner/stock.cc
index df6ccce..be4fcff 100644
--- a/owlps-positioner/stock.cc
+++ b/owlps-positioner/stock.cc
@@ -138,7 +138,7 @@ void Stock::waypoint_remove_building(const Waypoint &point,
 
   // If the Waypoint is not linked to any Building any more, we
   // delete it
-  if (waypoint->get_1st_building() == NULL)
+  if (! waypoint->get_1st_building())
     waypoints.erase(i) ;
 }
 
diff --git a/owlps-positioner/tests/testutil.cc b/owlps-positioner/tests/testutil.cc
index 55703eb..31bc8a9 100644
--- a/owlps-positioner/tests/testutil.cc
+++ b/owlps-positioner/tests/testutil.cc
@@ -146,7 +146,7 @@ void TestUtil::create_request_list()
 
   CalibrationRequest *calibration_request =
     dynamic_cast<CalibrationRequest*>(requests.at(1)) ;
-  if (calibration_request != NULL)
+  if (calibration_request)
     calibration_request->reference_point_backward_link() ;
 
   requests.push_back(new Request(&mobiles[0], timestamps[2],
@@ -162,7 +162,7 @@ void TestUtil::create_result_list()
       CalibrationRequest *calibration_request =
         dynamic_cast<CalibrationRequest*>(*i) ;
       Result result ;
-      if (calibration_request != NULL)
+      if (calibration_request)
         result = algo.compute(*calibration_request) ;
       else
         result = algo.compute(**i) ;
@@ -350,9 +350,9 @@ bool TestUtil::request_equals(const Request &first,
     return false ;
 
   // Compare mobile values
-  if (first.get_mobile() == NULL || second.get_mobile() == NULL)
+  if (! (first.get_mobile() && second.get_mobile()))
     {
-      if (first.get_mobile() != NULL || second.get_mobile() != NULL)
+      if (first.get_mobile() || second.get_mobile())
         return false ;
     }
   else if (*first.get_mobile() != *second.get_mobile())
@@ -406,9 +406,9 @@ bool TestUtil::measurement_equals(const Measurement &first,
     return false ;
 
   // Compare ap values
-  if (first.get_cp() == NULL || second.get_cp() == NULL)
+  if (! (first.get_cp() && second.get_cp()))
     {
-      if (first.get_cp() != NULL || second.get_cp() != NULL)
+      if (first.get_cp() || second.get_cp())
         return false ;
     }
   else if (*first.get_cp() != *second.get_cp())
diff --git a/owlps-positioner/waypoint.cc b/owlps-positioner/waypoint.cc
index bf41d8a..97bd383 100644
--- a/owlps-positioner/waypoint.cc
+++ b/owlps-positioner/waypoint.cc
@@ -35,7 +35,7 @@ Waypoint::Waypoint(Building *const _b,
                    const float _x, const float _y, const float _z):
   Point3D(_x, _y, _z)
 {
-  if (_b != NULL)
+  if (_b)
     buildings.insert(_b) ;
 }
 
@@ -47,7 +47,7 @@ Waypoint::Waypoint(Building *const _b,
  */
 Waypoint::Waypoint(Building *const _b, const Point3D &p): Point3D(p)
 {
-  if (_b != NULL)
+  if (_b)
     buildings.insert(_b) ;
 }
 
diff --git a/owlps-positioner/waypoint.hh b/owlps-positioner/waypoint.hh
index 5004637..640d902 100644
--- a/owlps-positioner/waypoint.hh
+++ b/owlps-positioner/waypoint.hh
@@ -115,7 +115,7 @@ Waypoint::get_buildings() const
  */
 inline void Waypoint::add_building(Building *const _b)
 {
-  if (_b != NULL)
+  if (_b)
     buildings.insert(_b) ;
 }
 
@@ -128,7 +128,7 @@ inline void Waypoint::add_buildings(const Waypoint &source)
 
 inline void Waypoint::remove_building(Building *const _b)
 {
-  if (_b != NULL)
+  if (_b)
     buildings.erase(_b) ;
 }