diff --git a/fasta.cabal b/fasta.cabal
--- a/fasta.cabal
+++ b/fasta.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.10.4.0
+version:             0.10.4.1
 
 -- A short (one-line) description of the package.
 synopsis:            A simple, mindless parser for fasta files.
diff --git a/src/Data/Fasta/ByteString/Lazy/Utility.hs b/src/Data/Fasta/ByteString/Lazy/Utility.hs
--- a/src/Data/Fasta/ByteString/Lazy/Utility.hs
+++ b/src/Data/Fasta/ByteString/Lazy/Utility.hs
@@ -10,8 +10,10 @@
                                           ) where
 
 -- Built in
+import Data.Maybe
 
 -- Cabal
+import Control.Lens
 import qualified Data.ByteString.Lazy.Char8 as BL
 
 -- Local
@@ -21,7 +23,10 @@
 -- | Gets a 1 indexed field from the header of a fasta sequence using a certain
 -- delimiter.
 getField :: Int -> Char -> FastaSequence -> BL.ByteString
-getField field delim = (!! (field - 1)) . BL.split delim . fastaHeader
+getField field delim = fromMaybe (error "getField: Field out of bounds in fasta header")
+                     . preview (ix $ field - 1)
+                     . BL.split delim
+                     . fastaHeader
 
 -- | Gets the complement of the sequence.
 compl :: FastaSequence -> FastaSequence
diff --git a/src/Data/Fasta/ByteString/Utility.hs b/src/Data/Fasta/ByteString/Utility.hs
--- a/src/Data/Fasta/ByteString/Utility.hs
+++ b/src/Data/Fasta/ByteString/Utility.hs
@@ -10,8 +10,10 @@
                                      ) where
 
 -- Built in
+import Data.Maybe
 
 -- Cabal
+import Control.Lens
 import qualified Data.ByteString.Char8 as B
 
 -- Local
@@ -21,7 +23,10 @@
 -- | Gets a 1 indexed field from the header of a fasta sequence using a certain
 -- delimiter.
 getField :: Int -> Char -> FastaSequence -> B.ByteString
-getField field delim = (!! (field - 1)) . B.split delim . fastaHeader
+getField field delim = fromMaybe (error "getField: Field out of bounds in fasta header")
+                     . preview (ix $ field - 1)
+                     . B.split delim
+                     . fastaHeader
 
 -- | Gets the complement of the sequence.
 compl :: FastaSequence -> FastaSequence
diff --git a/src/Data/Fasta/String/Utility.hs b/src/Data/Fasta/String/Utility.hs
--- a/src/Data/Fasta/String/Utility.hs
+++ b/src/Data/Fasta/String/Utility.hs
@@ -10,8 +10,10 @@
                                  ) where
 
 -- Built in
+import Data.Maybe
 
 -- Cabal
+import Control.Lens
 import qualified Data.List.Split as Split
 
 -- Local
@@ -21,7 +23,10 @@
 -- | Gets a 1 indexed field from the header of a fasta sequence using a certain
 -- delimiter.
 getField :: Int -> Char -> FastaSequence -> String
-getField field delim = (!! (field - 1)) . Split.splitWhen (== delim) . fastaHeader
+getField field delim = fromMaybe (error "getField: Field out of bounds in fasta header")
+                     . preview (ix $ field - 1)
+                     . Split.splitWhen (== delim)
+                     . fastaHeader
 
 -- | Gets the complement of the sequence.
 compl :: FastaSequence -> FastaSequence
diff --git a/src/Data/Fasta/Text/Lazy/Utility.hs b/src/Data/Fasta/Text/Lazy/Utility.hs
--- a/src/Data/Fasta/Text/Lazy/Utility.hs
+++ b/src/Data/Fasta/Text/Lazy/Utility.hs
@@ -10,8 +10,10 @@
                                     ) where
 
 -- Built in
+import Data.Maybe
 
 -- Cabal
+import Control.Lens
 import qualified Data.Text.Lazy as T
 
 -- Local
@@ -21,7 +23,10 @@
 -- | Gets a 1 indexed field from the header of a fasta sequence using a certain
 -- delimiter.
 getField :: Int -> Char -> FastaSequence -> T.Text
-getField field delim = (!! (field - 1)) . T.split (== delim) . fastaHeader
+getField field delim = fromMaybe (error "getField: Field out of bounds in fasta header")
+                     . preview (ix $ field - 1)
+                     . T.split (== delim)
+                     . fastaHeader
 
 -- | Gets the complement of the sequence.
 compl :: FastaSequence -> FastaSequence
diff --git a/src/Data/Fasta/Text/Utility.hs b/src/Data/Fasta/Text/Utility.hs
--- a/src/Data/Fasta/Text/Utility.hs
+++ b/src/Data/Fasta/Text/Utility.hs
@@ -10,8 +10,10 @@
                                ) where
 
 -- Built in
+import Data.Maybe
 
 -- Cabal
+import Control.Lens
 import qualified Data.Text as T
 
 -- Local
@@ -21,7 +23,10 @@
 -- | Gets a 1 indexed field from the header of a fasta sequence using a certain
 -- delimiter.
 getField :: Int -> Char -> FastaSequence -> T.Text
-getField field delim = (!! (field - 1)) . T.split (== delim) . fastaHeader
+getField field delim = fromMaybe (error "getField: Field out of bounds in fasta header")
+                     . preview (ix $ field - 1)
+                     . T.split (== delim)
+                     . fastaHeader
 
 -- | Gets the complement of the sequence.
 compl :: FastaSequence -> FastaSequence