diff --git a/news/deprecate-lattice-readstr-method.rst b/news/deprecate-lattice-readstr-method.rst
@@ -0,0 +1,25 @@
+**Added:**
+
+* Added ``read_structure`` method into ``PDFFitStructure`` class
+* Added ``cell_parms`` method into ``Lattice`` class
+
+**Changed:**
+
+* <news item>
+
+**Deprecated:**
+
+* Deprecated ``readStr`` method in ``PDFFitStructure`` class for removal in version 4.0.0
+* Deprecated ``abcABG`` method in ``Lattice`` class for removal in version 4.0.0
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>
diff --git a/src/diffpy/structure/lattice.py b/src/diffpy/structure/lattice.py
@@ -43,6 +43,12 @@
     "set_new_latt_base_vec",
     removal_version,
 )
+abcABG_deprecation_msg = build_deprecation_message(
+    base,
+    "abcABG",
+    "cell_parms",
+    removal_version,
+)
 
 # Helper Functions -----------------------------------------------------------
 
@@ -559,7 +565,16 @@ def set_new_latt_base_vec(self, base):
         )
         return
 
+    @deprecated(abcABG_deprecation_msg)
     def abcABG(self):
+        """'diffpy.structure.Lattice.abcABG' is deprecated and will be
+        removed in version 4.0.0.
+
+        Please use 'diffpy.structure.Lattice.cell_parms' instead.
+        """
+        return self.cell_parms()
+
+    def cell_parms(self):
         """Return the cell parameters in the standard setting.
 
         Returns

diff --git a/src/diffpy/structure/pdffitstructure.py b/src/diffpy/structure/pdffitstructure.py
@@ -79,6 +79,15 @@ def read(self, filename, format="auto"):
         return p
 
     def readStr(self, s, format="auto"):
+        """'diffpy.structure.PDFFitStructure.readStr' is deprecated and
+        will be removed in version 4.0.0.
+
+        Please use 'diffpy.structure.PDFFitStructure.read_structure'
+        instead.
+        """
+        return self.read_structure(s, format)
+
+    def read_structure(self, s, format="auto"):
         """Same as `Structure.readStr`, but update `spcgr` value in
         `self.pdffit` when parser can get spacegroup.
 

diff --git a/tests/test_lattice.py b/tests/test_lattice.py
@@ -50,7 +50,7 @@ def test___init__(self):
         L2 = Lattice(base=L0.base)
         self.assertTrue(numpy.array_equal(L0.base, L2.base))
         self.assertTrue(numpy.array_equal(L0.isotropicunit, L2.isotropicunit))
-        L3 = Lattice(*L0.abcABG(), baserot=L0.baserot)
+        L3 = Lattice(*L0.cell_parms(), baserot=L0.baserot)
         self.assertTrue(numpy.allclose(L0.base, L3.base))
         self.assertTrue(numpy.allclose(L0.isotropicunit, L3.isotropicunit))
         return
@@ -229,10 +229,10 @@ def test_set_lat_base(self):
     def test_reciprocal(self):
         """Check calculation of reciprocal lattice."""
         r1 = self.lattice.reciprocal()
-        self.assertEqual((1, 1, 1, 90, 90, 90), r1.abcABG())
+        self.assertEqual((1, 1, 1, 90, 90, 90), r1.cell_parms())
         L2 = Lattice(2, 4, 8, 90, 90, 90)
         r2 = L2.reciprocal()
-        self.assertEqual((0.5, 0.25, 0.125, 90, 90, 90), r2.abcABG())
+        self.assertEqual((0.5, 0.25, 0.125, 90, 90, 90), r2.cell_parms())
         rr2 = r2.reciprocal()
         self.assertTrue(numpy.array_equal(L2.base, rr2.base))
         return

diff --git a/tests/test_p_discus.py b/tests/test_p_discus.py
@@ -46,7 +46,7 @@ def test_read_discus_Ni(self):
         self.assertEqual("Fm-3m", stru.pdffit["spcgr"])
         # cell record
         abcABG = (3.52, 3.52, 3.52, 90.0, 90.0, 90.0)
-        self.assertEqual(abcABG, stru.lattice.abcABG())
+        self.assertEqual(abcABG, stru.lattice.cell_parms())
         # ncell
         self.assertEqual([1, 1, 1, 4], stru.pdffit["ncell"])
         self.assertEqual(4, len(stru))

diff --git a/tests/test_structure.py b/tests/test_structure.py
@@ -420,7 +420,7 @@ def test___imul__(self):
         self.assertEqual(0, len(self.stru))
         return
 
-    def test__get_lattice(self):
+    def test__get_lattice_dep(self):
         """Check Structure._get_lattice()"""
         lat = Lattice()
         stru = Structure()
@@ -429,6 +429,15 @@ def test__get_lattice(self):
         self.assertTrue(lat is stru2.lattice)
         return
 
+    def test__get_lattice(self):
+        """Check Structure._get_lattice()"""
+        lat = Lattice()
+        stru = Structure()
+        self.assertEqual((1, 1, 1, 90, 90, 90), stru.lattice.cell_parms())
+        stru2 = Structure(lattice=lat)
+        self.assertTrue(lat is stru2.lattice)
+        return
+
     def test__set_lattice(self):
         """Check Structure._set_lattice()"""
         lat = Lattice()

diff --git a/tests/test_supercell.py b/tests/test_supercell.py
@@ -59,8 +59,8 @@ def test_ni_supercell(self):
         """Check supercell expansion for Ni."""
         ni_123 = supercell(self.stru_ni, (1, 2, 3))
         self.assertEqual(6 * len(self.stru_ni), len(ni_123))
-        a, b, c = self.stru_ni.lattice.abcABG()[:3]
-        a1, b2, c3 = ni_123.lattice.abcABG()[:3]
+        a, b, c = self.stru_ni.lattice.cell_parms()[:3]
+        a1, b2, c3 = ni_123.lattice.cell_parms()[:3]
         self.assertAlmostEqual(a, a1, 8)
         self.assertAlmostEqual(b * 2, b2, 8)
         self.assertAlmostEqual(c * 3, c3, 8)