diff --git a/pymule/__init__.py b/pymule/__init__.py
index dcd57ecae579a2cbedf8ed723bdee82769aa9534..01195ed400f3159af180d900407131ae4e4100d8 100644
--- a/pymule/__init__.py
+++ b/pymule/__init__.py
@@ -10,3 +10,5 @@ from loader import importreg, pattern, setup, sigma,                          \
                    addsets, scaleset
 
 from plot import errorband
+
+from constants import pi, alpha, GF, conv, Mmu, Mel, Mtau
diff --git a/pymule/constants.py b/pymule/constants.py
new file mode 100644
index 0000000000000000000000000000000000000000..d0d1aad4bd604338620c5347421f7275f0038d30
--- /dev/null
+++ b/pymule/constants.py
@@ -0,0 +1,35 @@
+import numpy as np
+import os
+
+
+def read_globaldef(globaldef=""):
+    if len(globaldef) == 0:
+        dir_path = os.path.dirname(os.path.realpath(__file__))
+        globaldef = os.path.abspath(os.path.join(
+            dir_path, os.pardir, os.pardir, 'global_def.f95'
+        ))
+
+    if not os.path.exists(globaldef):
+        raise IOError("No such file or directory %s" % globaldef)
+
+    with open(globaldef) as fp:
+        return [
+            (n,eval(v))
+            for n,v in re.findall(
+                "parameter *:: *([A-Z][A-Z\d]*) = ([\dE\.+/-]+)",
+                fp.read(),
+                re.IGNORECASE
+            )
+        ]
+
+
+pi = np.pi
+
+Mmu = 105.6583715  # MeV
+Mel = 0.510998928  # MeV
+Mtau = 1776.82     # MeV
+
+alpha = 1./137.0359997
+GF = 1.16637E-11   # MeV^-2
+
+conv = 3.893793655569159807686738742e8  # MeV^2 mu barn