diff --git a/src/bench/bench.cpp b/src/bench/bench.cpp
index af3d152c9..8f9432e11 100644
--- a/src/bench/bench.cpp
+++ b/src/bench/bench.cpp
@@ -9,9 +9,7 @@
 #include <iomanip>
 #include <sys/time.h>
 
-using namespace benchmark;
-
-std::map<std::string, BenchFunction> BenchRunner::benchmarks;
+std::map<std::string, benchmark::BenchFunction> benchmark::BenchRunner::benchmarks;
 
 static double gettimedouble(void) {
     struct timeval tv;
@@ -19,29 +17,29 @@ static double gettimedouble(void) {
     return tv.tv_usec * 0.000001 + tv.tv_sec;
 }
 
-BenchRunner::BenchRunner(std::string name, BenchFunction func)
+benchmark::BenchRunner::BenchRunner(std::string name, benchmark::BenchFunction func)
 {
     benchmarks.insert(std::make_pair(name, func));
 }
 
 void
-BenchRunner::RunAll(double elapsedTimeForOne)
+benchmark::BenchRunner::RunAll(double elapsedTimeForOne)
 {
     perf_init();
     std::cout << "#Benchmark" << "," << "count" << "," << "min" << "," << "max" << "," << "average" << ","
               << "min_cycles" << "," << "max_cycles" << "," << "average_cycles" << "\n";
 
-    for (std::map<std::string,BenchFunction>::iterator it = benchmarks.begin();
+    for (std::map<std::string,benchmark::BenchFunction>::iterator it = benchmarks.begin();
          it != benchmarks.end(); ++it) {
 
         State state(it->first, elapsedTimeForOne);
-        BenchFunction& func = it->second;
+        benchmark::BenchFunction& func = it->second;
         func(state);
     }
     perf_fini();
 }
 
-bool State::KeepRunning()
+bool benchmark::State::KeepRunning()
 {
     if (count & countMask) {
       ++count;