diff --git a/Makefile b/Makefile
index 4d4c843..0264925 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,7 @@ kernel.o: src/kernel.c config.h
 mmu.o: src/mmu.c
 	gcc $(CCFLAGS) -c -o mmu.o src/mmu.c
 
-process.o: src/process.c
+process.o: src/process.c config.h
 	gcc $(CCFLAGS) -c -o process.o src/process.c
 
 random.o: src/random.c
diff --git a/config.h b/config.h
index 95a4f1a..cfb50ef 100644
--- a/config.h
+++ b/config.h
@@ -3,3 +3,5 @@
 #define WSCLOCK_TIME_WINDOW 1500
 
 #define VERBOSE_SANITY_CHECK 0
+
+#define WS_CHANGE_INVERSE_CHANCE 1000
diff --git a/src/process.c b/src/process.c
index 6dcc00d..e0b3b68 100644
--- a/src/process.c
+++ b/src/process.c
@@ -5,6 +5,8 @@
 #include "mmu.h"
 #include "random.h"
 
+#include "config.h"
+
 struct Process *
 Process(size_t proc_id, size_t max_accesses, size_t total_pages_owned, size_t ws_size)
 {
@@ -27,7 +29,8 @@ Process(size_t proc_id, size_t max_accesses, size_t total_pages_owned, size_t ws
 	return p;
 }
 
-size_t PROCESS_run_for(struct Process *p, size_t time_bits)
+size_t
+PROCESS_run_for(struct Process *p, size_t time_bits)
 {
 	if (!p) {
 		printf("[process ?] p == NULL, something is very wrong\n");
@@ -49,7 +52,19 @@ size_t PROCESS_run_for(struct Process *p, size_t time_bits)
 			printf("[process %d] Reading from page #%d\n", p->id, accessed_page_no);
 			MMU_read(p->pt, accessed_page_no);
 		}
+
+		if (!randint(WS_CHANGE_INVERSE_CHANCE))
+			PROCESS_change_working_set(p);
 	}
 
 	return p->pages_accessed >= p->max_accesses;
 }
+
+void
+PROCESS_change_working_set(struct Process *p)
+{
+	printf("[process %d] Changing working set after %d accesses\n", p->id, p->pages_accessed);
+
+	for (size_t i = 0; i < p->ws_size; i++)
+		p->ws[i] = randint(p->total_pages_owned);
+}