diff --git a/src/backscattering_analyzer/__init__.py b/src/backscattering_analyzer/__init__.py
new file mode 100644
index 0000000..db19a4b
--- /dev/null
+++ b/src/backscattering_analyzer/__init__.py
@@ -0,0 +1,3 @@
+from logging import getLogger
+
+logger = getLogger(__name__)
diff --git a/src/backscattering_analyzer/measurement.py b/src/backscattering_analyzer/measurement.py
new file mode 100644
index 0000000..15c8122
--- /dev/null
+++ b/src/backscattering_analyzer/measurement.py
@@ -0,0 +1,29 @@
+from backscattering_analyzer.bench import Bench
+from backscattering_analyzer.package.measurement import (
+    Measurement as Package,
+)
+
+
+class Measurement:
+    def __init__(self, package: Package):
+        self.name = package.metadata.name
+        self.description = package.metadata.description
+        self.injection_power = package.metadata.injection_power
+        self.dark_fringe_power = package.metadata.dark_fringe_power
+
+        self.benches: list[Bench] = []
+        for i in range(len(package.benches)):
+            bench = package.benches[i]
+            mirror = package.mirrors[i]
+            movement = (
+                bench.metadata.factor_calib * bench.signal
+                - mirror.metadata.factor_calib * mirror.signal
+            )
+            self.benches.append(
+                Bench(
+                    name=bench.metadata.name,
+                    fsc=bench.metadata.fsc,
+                    movement=movement,
+                )
+            )
+        self.sensitivity = package.sensitivity
diff --git a/src/backscattering_analyzer/sensitivity.py b/src/backscattering_analyzer/sensitivity.py
new file mode 100644
index 0000000..489bb10
--- /dev/null
+++ b/src/backscattering_analyzer/sensitivity.py
@@ -0,0 +1,5 @@
+from gwpy.frequencyseries import FrequencySeries
+
+
+class sensitivity(FrequencySeries):
+    pass