diff --git a/Common/processing.cpp b/Common/processing.cpp
index c3db8ec..9d18349 100644
--- a/Common/processing.cpp
+++ b/Common/processing.cpp
@@ -305,6 +305,11 @@ void ProcessingArray::DeleteAll()
 	ProcessArray.clear();
 }
 
+void ProcessingArray::PreProcess()
+{
+	for (size_t i=0; i<ProcessArray.size(); ++i) ProcessArray.at(i)->PreProcess();
+}
+
 int ProcessingArray::Process()
 {
 	int nextProcess=maxInterval;
@@ -318,6 +323,11 @@ int ProcessingArray::Process()
 	return nextProcess;
 }
 
+void ProcessingArray::PostProcess()
+{
+	for (size_t i=0; i<ProcessArray.size(); ++i) ProcessArray.at(i)->PostProcess();
+}
+
 void ProcessingArray::DumpBoxes2File( string vtkfilenameprefix ) const
 {
 	for (size_t i=0; i<ProcessArray.size(); ++i)
diff --git a/Common/processing.h b/Common/processing.h
index e25851b..c262420 100644
--- a/Common/processing.h
+++ b/Common/processing.h
@@ -64,8 +64,16 @@ public:
 	void AddFrequency(vector<double> *freqs);
 
 	bool CheckTimestep();
+
+	//! Process data prior to the simulation run.
+	virtual void PreProcess() {};
+
+	//! Process data during simulation run.
 	virtual int Process() {return GetNextInterval();}
 
+	//! Process data after simulation has finished.
+	virtual void PostProcess() {};
+
 	//! If disabled, Process() will do nothing...
 	virtual void SetEnable(bool val) {Enabled=val;}
 	//! If disabled, Process() will do nothing...
@@ -152,8 +160,15 @@ public:
 	//! Deletes all given processing's, can be helpful, but use carefull!!!
 	void DeleteAll();
 
+	//! Invoke PreProcess() on all Processings.
+	void PreProcess();
+
+	//! Invoke Process() on all Processings. Will return the smallest next iteration interval.
 	int Process();
 
+	//! Invoke PostProcess() on all Processings.
+	void PostProcess();
+
 	void DumpBoxes2File( string vtkfilenameprefix ) const;
 
 protected:
diff --git a/openems.cpp b/openems.cpp
index 9d44726..b57565d 100644
--- a/openems.cpp
+++ b/openems.cpp
@@ -617,6 +617,7 @@ void openEMS::RunFDTD()
 
 	//*************** simulate ************//
 
+	PA->PreProcess();
 	int step=PA->Process();
 	if ((step<0) || (step>(int)NrTS)) step=NrTS;
 	while ((FDTD_Eng->GetNumberOfTimesteps()<NrTS) && (change>endCrit) && !CheckAbortCond())
@@ -654,6 +655,7 @@ void openEMS::RunFDTD()
 			PA->FlushNext();
 		}
 	}
+	PA->PostProcess();
 
 	//*************** postproc ************//
 	prevTime = currTime;